Patent Description:
Service mapping is a set of operations through which the remote network management platform can discover and organize these computing devices and applications, and represent the relationships therebetween. Service mapping facilitates the representation of the hardware and software components that jointly provide a service in a managed network. A remote network management platform can maintain a service model that represents the computing devices of a managed network, applications of the managed network, and relationships therebetween. From time to time, this service model may be updated as the hardware and software components contributing to the service change, or in order to correct part of the service model.

For some managed networks, the process of updating a service model can consume significant processing resources, thereby negatively affecting the performance of the remote network management platform. Improvements are therefore desired. <CIT> is directed to systems and methods for processing alerts indicative of conditions of nodes of a computing infrastructure, comprising generating a node hierarchy having nodes associated with a service model, wherein relationships between the nodes are based on impact rules, identifying alerts related to the node hierarchy, wherein the alerts are indicative of impairments affecting at least a portion of the node hierarchy, and performing impact calculation for nodes of the node hierarchy based on the identified alerts.

The service model for a managed network can represent any devices on the managed network, any applications or services executing thereon, as well as relationships between devices, applications, and services. Each of the devices, applications, and/or services can be referred to as configuration items (CIs). Further, each CI can be represented by a corresponding CI record in a configuration management database (CMDB).

One way to maintain a service model for such a managed network is to re-compute the services of the managed network using a re-computation process as CI records of the CMDB change. The re-computation process can synchronize the CMDB with the service model by persisting changes in the CMDB into the service model. For a change affecting a given CI, the re-computation process can involve updating the information for the given CI in the service model, and also re-building the topology of the service model based on relations between the given CI and other CIs of the CMDB. Re-building the topology can involve identifying an entry point of a service to which the given CI relates, tracing the entry point to the given CI based on a set of relations between the given CI and the entry point, and resolving the set of relations into a graph.

Unfortunately, however, this re-computation process can be wasteful in terms of consumption of memory and processing resources. For instance, for a CI change that does not affect a topology of the service model, re-building the topology of the service model may be unnecessary.

The embodiments herein address this and potentially other problems by varying the manner in which a service model is re-computed depending on a type of change that is made to a CI record. When a change is made to a CI record of a CMDB, a server device can add a change record corresponding to the change to a change record table. The change record can specify a change type that is indicative of whether the change affects a topology of service model. The server device can use the change type specified in the change record as a basis for selecting a service model re-computation mode from among a plurality of service model recomputation modes, and re-compute a service layer of the service model in accordance with the selected service model re-computation mode.

Accordingly, a first example embodiment involves a system including a database that contains a plurality of CI records corresponding to a set of computing devices disposed within a managed network, a set of software applications configured to execute on the set of computing devices, and a network-based service that is provided by execution of the set of software applications. The managed network is associated with the computational instance. Further, the database contains a definition of a service model that represents the set of computing devices, the set of software applications, and relationships therebetween that facilitate providing the network-based service. The service model includes a service environment having multiple service layers that are hierarchically-arranged within the service environment. The system also includes one or more server devices configured to receive, from the managed network, an indication of a change to a CI record of the plurality of CI records. The one or more server devices are also configured to store, in the database, the CI record as changed and add, to a change record table stored within the database, a change record corresponding to the change to the CI record. The change record references the CI record and a service layer of the multiple service layers, and specifies a change type that is indicative of whether the change affects a topology of the service model. The one or more server devices are also configured to select, for the service layer based on the change type, a service model recomputation mode from among a plurality of service model re-computation modes, wherein selecting the service model (<NUM>) re-computation mode comprises: in response to the change type indicating that the change does not affect the topology of the service model, selecting a fast re-computation mode; and in response to the change type indicating the change does affect the topology of the service model, selecting a full re-computation mode. And the one or more server devices are configured to re-compute the service layer of the service environment in accordance with the selected service model re-computation mode.

In a second example embodiment, a method involves maintaining, by one or more server devices of a computational instance, a database that contains a plurality of CI records corresponding to a set of computing devices within a managed network, a set of software applications configured to execute on the set of computing devices, and a network-based service that is provided by execution of the set of software applications. The managed network is associated with the computational instance. Further, the database contains a definition of a service model that represents the set of computing devices, the set of software applications, and relationships therebetween that facilitate providing the network-based service. The service model includes a service environment having multiple service layers that are hierarchically-arranged. The method also involves receiving, by the one or more server devices, from the managed network, an indication of a change to a CI record of the plurality of CI records. In addition, the method involves storing, in the database, the CI record as changed and adding, by the one or more server devices, to a change record table stored within the database, a change record corresponding to the change to the CI record. The change record references the CI record and a service layer of the multiple service layers, and specifies a change type that is indicative of whether the change affects a topology of the service model. Further, the method involves selecting, by the one or more server devices based on the change type, for the service layer, a service model re-computation mode from among a plurality of service model recomputation modes, wherein selecting the service model re-computation mode comprises: in response to the change type indicating that the change does not affect the topology of the service model, selecting a fast re-computation mode; and in response to the change type indicating the change does affect the topology of the service model, selecting a full recomputation mode. And the method involves re-computing, by the one or more server devices, the service layer of the service environment in accordance with the selected service model recomputation mode.

In a third example embodiment, an article of manufacture may include a non-transitory computer-readable medium, having stored thereon program instructions that, upon execution by one or more server devices of a computational instance of a remote network management platform, cause the one or more server devices to perform operations in accordance with the second example embodiment.

In a further example, a computing system may include at least one processor, as well as memory and program instructions. The program instructions may be stored in the memory, and upon execution by the at least one processor, cause the computing system to perform operations in accordance with the second example embodiment.

In a further example, a system may include various means for carrying out each of the operations of the second example embodiment.

These, as well as other embodiments, aspects, advantages, and alternatives, will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference where appropriate to the accompanying drawings. Further, this summary and other descriptions and figures provided herein are intended to illustrate embodiments by way of example only and, as such, that numerous variations are possible. For instance, structural elements and process steps can be rearranged, combined, distributed, eliminated, or otherwise changed, while remaining within the scope of the embodiments as claimed.

Example methods, devices, and systems are described herein. It should be understood that the words "example" and "exemplary" are used herein to mean "serving as an example, instance, or illustration. " Any embodiment or feature described herein as being an "example" or "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or features unless stated as such. Thus, other embodiments can be utilized and other changes can be made without departing from the scope of the claims.

Accordingly, the example embodiments described herein are not meant to be limiting. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations. For example, the separation of features into "client" and "server" components may occur in a number of ways.

A large enterprise is a complex entity with many interrelated operations. Some of these are found across the enterprise, such as human resources (HR), supply chain, information technology (IT), and finance. However, each enterprise also has its own unique operations that provide essential capabilities and/or create competitive advantages.

To support widely-implemented operations, enterprises typically use off-the-shelf software applications, such as customer relationship management (CRM) and human capital management (HCM) packages. However, they may also need custom software applications to meet their own unique requirements. A large enterprise often has dozens or hundreds of these custom software applications. Nonetheless, the advantages provided by the embodiments herein are not limited to large enterprises and may be applicable to an enterprise, or any other type of organization, of any size.

Many such software applications are developed by individual departments within the enterprise. These range from simple spreadsheets to custom-built software tools and databases. But the proliferation of siloed custom software applications has numerous disadvantages. It negatively impacts an enterprise's ability to run and grow its operations, innovate, and meet regulatory requirements. The enterprise may find it difficult to integrate, streamline and enhance its operations due to lack of a single system that unifies its subsystems and data.

To efficiently create custom applications, enterprises would benefit from a remotely-hosted application platform that eliminates unnecessary development complexity. The goal of such a platform would be to reduce time-consuming, repetitive application development tasks so that software engineers and individuals in other roles can focus on developing unique, high-value features.

In order to achieve this goal, the concept of Application Platform as a Service (aPaaS) is introduced, to intelligently automate workflows throughout the enterprise. An aPaaS system is hosted remotely from the enterprise, but may access data, applications, and services within the enterprise by way of secure connections. Such an aPaaS system may have a number of advantageous capabilities and characteristics. These advantages and characteristics may be able to improve the enterprise's operations and workflow for IT, HR, CRM, customer service, application development, and security.

The aPaaS system may support development and execution of model-view-controller (MVC) applications. MVC applications divide their functionality into three interconnected parts (model, view, and controller) in order to isolate representations of information from the manner in which the information is presented to the user, thereby allowing for efficient code reuse and parallel development. These applications may be web-based, and offer create, read, update, delete (CRUD) capabilities. This allows new applications to be built on a common application infrastructure.

The aPaaS system may support standardized application components, such as a standardized set of widgets for graphical user interface (GUI) development. In this way, applications built using the aPaaS system have a common look and feel. Other software components and modules may be standardized as well. In some cases, this look and feel can be branded or skinned with an enterprise's custom logos and/or color schemes.

The aPaaS system may support the ability to configure the behavior of applications using metadata. This allows application behaviors to be rapidly adapted to meet specific needs. Such an approach reduces development time and increases flexibility. Further, the aPaaS system may support GUI tools that facilitate metadata creation and management, thus reducing errors in the metadata.

The aPaaS system may support clearly-defined interfaces between applications, so that software developers can avoid unwanted inter-application dependencies. Thus, the aPaaS system may implement a service layer in which persistent state information and other data are stored.

The aPaaS system may support a rich set of integration features so that the applications thereon can interact with legacy applications and third-party applications. For instance, the aPaaS system may support a custom employee-onboarding system that integrates with legacy HR, IT, and accounting systems.

The aPaaS system may support enterprise-grade security. Furthermore, since the aPaaS system may be remotely hosted, it should also utilize security procedures when it interacts with systems in the enterprise or third-party networks and services hosted outside of the enterprise. For example, the aPaaS system may be configured to share data amongst the enterprise and other parties to detect and identify common security threats.

Other features, functionality, and advantages of an aPaaS system may exist. This description is for purpose of example and is not intended to be limiting.

As an example of the aPaaS development process, a software developer may be tasked to create a new application using the aPaaS system. First, the developer may define the data model, which specifies the types of data that the application uses and the relationships therebetween. Then, via a GUI of the aPaaS system, the developer enters (e.g., uploads) the data model. The aPaaS system automatically creates all of the corresponding database tables, fields, and relationships, which can then be accessed via an object-oriented services layer.

In addition, the aPaaS system can also build a fully-functional MVC application with client-side interfaces and server-side CRUD logic. This generated application may serve as the basis of further development for the user. Advantageously, the developer does not have to spend a large amount of time on basic application functionality. Further, since the application may be web-based, it can be accessed from any Internet-enabled client device. Alternatively or additionally, a local copy of the application may be able to be accessed, for instance, when Internet service is not available.

The aPaaS system may also support a rich set of pre-defined functionality that can be added to applications. These features include support for searching, email, templating, workflow design, reporting, analytics, social media, scripting, mobile-friendly output, and customized GUIs.

The following embodiments describe architectural and functional aspects of example aPaaS systems, as well as the features and advantages thereof.

<FIG> is a simplified block diagram exemplifying a computing device <NUM>, illustrating some of the components that could be included in a computing device arranged to operate in accordance with the embodiments herein. Computing device <NUM> could be a client device (e.g., a device actively operated by a user), a server device (e.g., a device that provides computational services to client devices), or some other type of computational platform. Some server devices may operate as client devices from time to time in order to perform particular operations, and some client devices may incorporate server features.

In this example, computing device <NUM> includes processor <NUM>, memory <NUM>, network interface <NUM>, and an input / output unit <NUM>, all of which may be coupled by a system bus <NUM> or a similar mechanism. In some embodiments, computing device <NUM> may include other components and/or peripheral devices (e.g., detachable storage, printers, and so on).

Processor <NUM> may be one or more of any type of computer processing element, such as a central processing unit (CPU), a co-processor (e.g., a mathematics, graphics, or encryption co-processor), a digital signal processor (DSP), a network processor, and/or a form of integrated circuit or controller that performs processor operations. In some cases, processor <NUM> may be one or more single-core processors. In other cases, processor <NUM> may be one or more multi-core processors with multiple independent processing units. Processor <NUM> may also include register memory for temporarily storing instructions being executed and related data, as well as cache memory for temporarily storing recently-used instructions and data.

Memory <NUM> may be any form of computer-usable memory, including but not limited to random access memory (RAM), read-only memory (ROM), and non-volatile memory (e.g., flash memory, hard disk drives, solid state drives, compact discs (CDs), digital video discs (DVDs), and/or tape storage). Thus, memory <NUM> represents both main memory units, as well as long-term storage. Other types of memory may include biological memory.

Memory <NUM> may store program instructions and/or data on which program instructions may operate. By way of example, memory <NUM> may store these program instructions on a non-transitory, computer-readable medium, such that the instructions are executable by processor <NUM> to carry out any of the methods, processes, or operations disclosed in this specification or the accompanying drawings.

As shown in <FIG>, memory <NUM> may include firmware 104A, kernel 104B, and/or applications 104C. Firmware 104A may be program code used to boot or otherwise initiate some or all of computing device <NUM>. Kernel 104B may be an operating system, including modules for memory management, scheduling and management of processes, input / output, and communication. Kernel 104B may also include device drivers that allow the operating system to communicate with the hardware modules (e.g., memory units, networking interfaces, ports, and busses), of computing device <NUM>. Applications 104C may be one or more user-space software programs, such as web browsers or email clients, as well as any software libraries used by these programs. Memory <NUM> may also store data used by these and other programs and applications.

Network interface <NUM> may take the form of one or more wireline interfaces, such as Ethernet (e.g., Fast Ethernet, Gigabit Ethernet, and so on). Network interface <NUM> may also support communication over one or more non-Ethernet media, such as coaxial cables or power lines, or over wide-area media, such as Synchronous Optical Networking (SONET) or digital subscriber line (DSL) technologies. Network interface <NUM> may additionally take the form of one or more wireless interfaces, such as IEEE <NUM> (Wifi), BLUETOOTH®, global positioning system (GPS), or a wide-area wireless interface. However, other forms of physical layer interfaces and other types of standard or proprietary communication protocols may be used over network interface <NUM>. Furthermore, network interface <NUM> may comprise multiple physical interfaces. For instance, some embodiments of computing device <NUM> may include Ethernet, BLUETOOTH®, and Wifi interfaces.

Input / output unit <NUM> may facilitate user and peripheral device interaction with computing device <NUM>. Input / output unit <NUM> may include one or more types of input devices, such as a keyboard, a mouse, a touch screen, and so on. Similarly, input / output unit <NUM> may include one or more types of output devices, such as a screen, monitor, printer, and/or one or more light emitting diodes (LEDs). Additionally or alternatively, computing device <NUM> may communicate with other devices using a universal serial bus (USB) or high-definition multimedia interface (HDMI) port interface, for example.

In some embodiments, one or more computing devices like computing device <NUM> may be deployed to support an aPaaS architecture. The exact physical location, connectivity, and configuration of these computing devices may be unknown and/or unimportant to client devices. Accordingly, the computing devices may be referred to as "cloud-based" devices that may be housed at various remote data center locations.

<FIG> depicts a cloud-based server cluster <NUM> in accordance with example embodiments. In <FIG>, operations of a computing device (e.g., computing device <NUM>) may be distributed between server devices <NUM>, data storage <NUM>, and routers <NUM>, all of which may be connected by local cluster network <NUM>. The number of server devices <NUM>, data storages <NUM>, and routers <NUM> in server cluster <NUM> may depend on the computing task(s) and/or applications assigned to server cluster <NUM>.

For example, server devices <NUM> can be configured to perform various computing tasks of computing device <NUM>. Thus, computing tasks can be distributed among one or more of server devices <NUM>. To the extent that these computing tasks can be performed in parallel, such a distribution of tasks may reduce the total time to complete these tasks and return a result. For purpose of simplicity, both server cluster <NUM> and individual server devices <NUM> may be referred to as a "server device. " This nomenclature should be understood to imply that one or more distinct server devices, data storage devices, and cluster routers may be involved in server device operations.

Data storage <NUM> may be data storage arrays that include drive array controllers configured to manage read and write access to groups of hard disk drives and/or solid state drives. The drive array controllers, alone or in conjunction with server devices <NUM>, may also be configured to manage backup or redundant copies of the data stored in data storage <NUM> to protect against drive failures or other types of failures that prevent one or more of server devices <NUM> from accessing units of data storage <NUM>. Other types of memory aside from drives may be used.

Routers <NUM> may include networking equipment configured to provide internal and external communications for server cluster <NUM>. For example, routers <NUM> may include one or more packet-switching and/or routing devices (including switches and/or gateways) configured to provide (i) network communications between server devices <NUM> and data storage <NUM> via local cluster network <NUM>, and/or (ii) network communications between the server cluster <NUM> and other devices via communication link <NUM> to network <NUM>.

Additionally, the configuration of routers <NUM> can be based at least in part on the data communication requirements of server devices <NUM> and data storage <NUM>, the latency and throughput of the local cluster network <NUM>, the latency, throughput, and cost of communication link <NUM>, and/or other factors that may contribute to the cost, speed, fault-tolerance, resiliency, efficiency and/or other design goals of the system architecture.

As a possible example, data storage <NUM> may include any form of database, such as a structured query language (SQL) database. Various types of data structures may store the information in such a database, including but not limited to tables, arrays, lists, trees, and tuples. Furthermore, any databases in data storage <NUM> may be monolithic or distributed across multiple physical devices.

Server devices <NUM> may be configured to transmit data to and receive data from data storage <NUM>. This transmission and retrieval may take the form of SQL queries or other types of database queries, and the output of such queries, respectively. Additional text, images, video, and/or audio may be included as well. Furthermore, server devices <NUM> may organize the received data into web page representations. Such a representation may take the form of a markup language, such as the hypertext markup language (HTML), the extensible markup language (XML), or some other standardized or proprietary format. Moreover, server devices <NUM> may have the capability of executing various types of computerized scripting languages, such as but not limited to Perl, Python, PHP Hypertext Preprocessor (PHP), Active Server Pages (ASP), JavaScript, and so on. Computer program code written in these languages may facilitate the providing of web pages to client devices, as well as client device interaction with the web pages.

<FIG> depicts a remote network management architecture, in accordance with example embodiments. This architecture includes three main components, managed network <NUM>, remote network management platform <NUM>, and third-party networks <NUM>, all connected by way of Internet <NUM>.

Managed network <NUM> may be, for example, an enterprise network used by an entity for computing and communications tasks, as well as storage of data. Thus, managed network <NUM> may include various client devices <NUM>, server devices <NUM>, routers <NUM>, virtual machines <NUM>, firewall <NUM>, and/or proxy servers <NUM>. Client devices <NUM> may be embodied by computing device <NUM>, server devices <NUM> may be embodied by computing device <NUM> or server cluster <NUM>, and routers <NUM> may be any type of router, switch, or gateway.

Virtual machines <NUM> may be embodied by one or more of computing device <NUM> or server cluster <NUM>. In general, a virtual machine is an emulation of a computing system, and mimics the functionality (e.g., processor, memory, and communication resources) of a physical computer. One physical computing system, such as server cluster <NUM>, may support up to thousands of individual virtual machines. In some embodiments, virtual machines <NUM> may be managed by a centralized server device or application that facilitates allocation of physical computing resources to individual virtual machines, as well as performance and error reporting. Enterprises often employ virtual machines in order to allocate computing resources in an efficient, as needed fashion. Providers of virtualized computing systems include VMWARE® and MICROSOFT®.

Firewall <NUM> may be one or more specialized routers or server devices that protect managed network <NUM> from unauthorized attempts to access the devices, applications, and services therein, while allowing authorized communication that is initiated from managed network <NUM>. Firewall <NUM> may also provide intrusion detection, web filtering, virus scanning, application-layer gateways, and other applications or services. In some embodiments not shown in <FIG>, managed network <NUM> may include one or more virtual private network (VPN) gateways with which it communicates with remote network management platform <NUM> (see below).

Managed network <NUM> may also include one or more proxy servers <NUM>. An embodiment of proxy servers <NUM> may be a server device that facilitates communication and movement of data between managed network <NUM>, remote network management platform <NUM>, and third-party networks <NUM>. In particular, proxy servers <NUM> may be able to establish and maintain secure communication sessions with one or more computational instances of remote network management platform <NUM>. By way of such a session, remote network management platform <NUM> may be able to discover and manage aspects of the architecture and configuration of managed network <NUM> and its components. Possibly with the assistance of proxy servers <NUM>, remote network management platform <NUM> may also be able to discover and manage aspects of third-party networks <NUM> that are used by managed network <NUM>.

Firewalls, such as firewall <NUM>, typically deny all communication sessions that are incoming by way of Internet <NUM>, unless such a session was ultimately initiated from behind the firewall (i.e., from a device on managed network <NUM>) or the firewall has been explicitly configured to support the session. By placing proxy servers <NUM> behind firewall <NUM> (e.g., within managed network <NUM> and protected by firewall <NUM>), proxy servers <NUM> may be able to initiate these communication sessions through firewall <NUM>. Thus, firewall <NUM> might not have to be specifically configured to support incoming sessions from remote network management platform <NUM>, thereby avoiding potential security risks to managed network <NUM>.

In some cases, managed network <NUM> may consist of a few devices and a small number of networks. In other deployments, managed network <NUM> may span multiple physical locations and include hundreds of networks and hundreds of thousands of devices. Thus, the architecture depicted in <FIG> is capable of scaling up or down by orders of magnitude.

Furthermore, depending on the size, architecture, and connectivity of managed network <NUM>, a varying number of proxy servers <NUM> may be deployed therein. For example, each one of proxy servers <NUM> may be responsible for communicating with remote network management platform <NUM> regarding a portion of managed network <NUM>. Alternatively or additionally, sets of two or more proxy servers may be assigned to such a portion of managed network <NUM> for purposes of load balancing, redundancy, and/or high availability.

Remote network management platform <NUM> is a hosted environment that provides aPaaS services to users, particularly to the operators of managed network <NUM>. These services may take the form of web-based portals, for instance. Thus, a user can securely access remote network management platform <NUM> from, for instance, client devices <NUM>, or potentially from a client device outside of managed network <NUM>. By way of the web-based portals, users may design, test, and deploy applications, generate reports, view analytics, and perform other tasks.

As shown in <FIG>, remote network management platform <NUM> includes four computational instances <NUM>, <NUM>, <NUM>, and <NUM>. Each of these instances may represent one or more server devices and/or one or more databases that provide a set of web portals, services, and applications (e.g., a wholly-functioning aPaaS system) available to a particular customer. In some cases, a single customer may use multiple computational instances. For example, managed network <NUM> may be an enterprise customer of remote network management platform <NUM>, and may use computational instances <NUM>, <NUM>, and <NUM>. The reason for providing multiple instances to one customer is that the customer may wish to independently develop, test, and deploy its applications and services. Thus, computational instance <NUM> may be dedicated to application development related to managed network <NUM>, computational instance <NUM> may be dedicated to testing these applications, and computational instance <NUM> may be dedicated to the live operation of tested applications and services. A computational instance may also be referred to as a hosted instance, a remote instance, a customer instance, or by some other designation. Any application deployed onto a computational instance may be a scoped application, in that its access to databases within the computational instance can be restricted to certain elements therein (e.g., one or more particular database tables or particular rows with one or more database tables).

For purpose of clarity, the disclosure herein refers to the physical hardware, software, and arrangement thereof as a "computational instance. " Note that users may colloquially refer to the graphical user interfaces provided thereby as "instances. " But unless it is defined otherwise herein, a "computational instance" is a computing system disposed within remote network management platform <NUM>.

The multi-instance architecture of remote network management platform <NUM> is in contrast to conventional multi-tenant architectures, over which multi-instance architectures have several advantages. In multi-tenant architectures, data from different customers (e.g., enterprises) are comingled in a single database. While these customers' data are separate from one another, the separation is enforced by the software that operates the single database. As a consequence, a security breach in this system may impact all customers' data, creating additional risk, especially for entities subject to governmental, healthcare, and/or financial regulation. Furthermore, any database operations that impact one customer will likely impact all customers sharing that database. Thus, if there is an outage due to hardware or software errors, this outage affects all such customers. Likewise, if the database is to be upgraded to meet the needs of one customer, it will be unavailable to all customers during the upgrade process. Often, such maintenance windows will be long, due to the size of the shared database.

In contrast, the multi-instance architecture provides each customer with its own database in a dedicated computing instance. This prevents comingling of customer data, and allows each instance to be independently managed. For example, when one customer's instance experiences an outage due to errors or an upgrade, other computational instances are not impacted. Maintenance down time is limited because the database only contains one customer's data. Further, the simpler design of the multi-instance architecture allows redundant copies of each customer database and instance to be deployed in a geographically diverse fashion. This facilitates high availability, where the live version of the customer's instance can be moved when faults are detected or maintenance is being performed.

In some embodiments, remote network management platform <NUM> may include one or more central instances, controlled by the entity that operates this platform. Like a computational instance, a central instance may include some number of physical or virtual servers and database devices. Such a central instance may serve as a repository for data that can be shared amongst at least some of the computational instances. For instance, definitions of common security threats that could occur on the computational instances, software packages that are commonly discovered on the computational instances, and/or an application store for applications that can be deployed to the computational instances may reside in a central instance. Computational instances may communicate with central instances by way of well-defined interfaces in order to obtain this data.

In order to support multiple computational instances in an efficient fashion, remote network management platform <NUM> may implement a plurality of these instances on a single hardware platform. For example, when the aPaaS system is implemented on a server cluster such as server cluster <NUM>, it may operate a virtual machine that dedicates varying amounts of computational, storage, and communication resources to instances. But full virtualization of server cluster <NUM> might not be necessary, and other mechanisms may be used to separate instances. In some examples, each instance may have a dedicated account and one or more dedicated databases on server cluster <NUM>. Alternatively, computational instance <NUM> may span multiple physical devices.

In some cases, a single server cluster of remote network management platform <NUM> may support multiple independent enterprises. Furthermore, as described below, remote network management platform <NUM> may include multiple server clusters deployed in geographically diverse data centers in order to facilitate load balancing, redundancy, and/or high availability.

Third-party networks <NUM> may be remote server devices (e.g., a plurality of server clusters such as server cluster <NUM>) that can be used for outsourced computational, data storage, communication, and service hosting operations. These servers may be virtualized (i.e., the servers may be virtual machines). Examples of third-party networks <NUM> may include AMAZON WEB SERVICES® and MICROSOFT® Azure. Like remote network management platform <NUM>, multiple server clusters supporting third-party networks <NUM> may be deployed at geographically diverse locations for purposes of load balancing, redundancy, and/or high availability.

Managed network <NUM> may use one or more of third-party networks <NUM> to deploy applications and services to its clients and customers. For instance, if managed network <NUM> provides online music streaming services, third-party networks <NUM> may store the music files and provide web interface and streaming capabilities. In this way, the enterprise of managed network <NUM> does not have to build and maintain its own servers for these operations.

Remote network management platform <NUM> may include modules that integrate with third-party networks <NUM> to expose virtual machines and managed services therein to managed network <NUM>. The modules may allow users to request virtual resources and provide flexible reporting for third-party networks <NUM>. In order to establish this functionality, a user from managed network <NUM> might first establish an account with third-party networks <NUM>, and request a set of associated resources. Then, the user may enter the account information into the appropriate modules of remote network management platform <NUM>. These modules may then automatically discover the manageable resources in the account, and also provide reports related to usage, performance, and billing.

Internet <NUM> may represent a portion of the global Internet. However, Internet <NUM> may alternatively represent a different type of network, such as a private wide-area or local-area packet-switched network.

<FIG> further illustrates the communication environment between managed network <NUM> and computational instance <NUM>, and introduces additional features and alternative embodiments. In <FIG>, computational instance <NUM> is replicated across data centers 400A and 400B. These data centers may be geographically distant from one another, perhaps in different cities or different countries. Each data center includes support equipment that facilitates communication with managed network <NUM>, as well as remote users.

In data center 400A, network traffic to and from external devices flows either through VPN gateway 402A or firewall 404A. VPN gateway 402A may be peered with VPN gateway <NUM> of managed network <NUM> by way of a security protocol such as Internet Protocol Security (IPSEC) or Transport Layer Security (TLS). Firewall 404A may be configured to allow access from authorized users, such as user <NUM> and remote user <NUM>, and to deny access to unauthorized users. By way of firewall 404A, these users may access computational instance <NUM>, and possibly other computational instances. Load balancer 406A may be used to distribute traffic amongst one or more physical or virtual server devices that host computational instance <NUM>. Load balancer 406A may simplify user access by hiding the internal configuration of data center 400A, (e.g., computational instance <NUM>) from client devices. For instance, if computational instance <NUM> includes multiple physical or virtual computing devices that share access to multiple databases, load balancer 406A may distribute network traffic and processing tasks across these computing devices and databases so that no one computing device or database is significantly busier than the others. In some embodiments, computational instance <NUM> may include VPN gateway 402A, firewall 404A, and load balancer 406A.

Data center 400B may include its own versions of the components in data center 400A. Thus, VPN gateway 402B, firewall 404B, and load balancer 406B may perform the same or similar operations as VPN gateway 402A, firewall 404A, and load balancer 406A, respectively. Further, by way of real-time or near-real-time database replication and/or other operations, computational instance <NUM> may exist simultaneously in data centers 400A and 400B.

Data centers 400A and 400B as shown in <FIG> may facilitate redundancy and high availability. In the configuration of <FIG>, data center 400A is active and data center 400B is passive. Thus, data center 400A is serving all traffic to and from managed network <NUM>, while the version of computational instance <NUM> in data center 400B is being updated in near-real-time. Other configurations, such as one in which both data centers are active, may be supported.

Should data center 400A fail in some fashion or otherwise become unavailable to users, data center 400B can take over as the active data center. For example, domain name system (DNS) servers that associate a domain name of computational instance <NUM> with one or more Internet Protocol (IP) addresses of data center 400A may re-associate the domain name with one or more IP addresses of data center 400B. After this re-association completes (which may take less than one second or several seconds), users may access computational instance <NUM> by way of data center 400B.

<FIG> also illustrates a possible configuration of managed network <NUM>. As noted above, proxy servers <NUM> and user <NUM> may access computational instance <NUM> through firewall <NUM>. Proxy servers <NUM> may also access configuration items <NUM>. In <FIG>, configuration items <NUM> may refer to any or all of client devices <NUM>, server devices <NUM>, routers <NUM>, and virtual machines <NUM>, any applications or services executing thereon, as well as relationships between devices, applications, and services. Thus, the term "configuration items" may be shorthand for any physical or virtual device, or any application or service remotely discoverable or managed by computational instance <NUM>, or relationships between discovered devices, applications, and services. Configuration items may be represented in a CMDB of computational instance <NUM>.

As noted above, VPN gateway <NUM> may provide a dedicated VPN to VPN gateway 402A. Such a VPN may be helpful when there is a significant amount of traffic between managed network <NUM> and computational instance <NUM>, or security policies otherwise suggest or require use of a VPN between these sites. In some embodiments, any device in managed network <NUM> and/or computational instance <NUM> that directly communicates via the VPN is assigned a public IP address. Other devices in managed network <NUM> and/or computational instance <NUM> may be assigned private IP addresses (e.g., IP addresses selected from the <NUM>. <NUM> - <NUM>. <NUM> or <NUM>. <NUM> - <NUM>. <NUM> ranges, represented in shorthand as subnets <NUM>. <NUM>/<NUM> and <NUM>. <NUM>/<NUM>, respectively).

In order for remote network management platform <NUM> to administer the devices, applications, and services of managed network <NUM>, remote network management platform <NUM> may first determine what devices are present in managed network <NUM>, the configurations and operational statuses of these devices, and the applications and services provided by the devices, and well as the relationships between discovered devices, applications, and services. As noted above, each device, application, service, and relationship may be referred to as a configuration item. The process of defining configuration items within managed network <NUM> is referred to as discovery, and may be facilitated at least in part by proxy servers <NUM>.

For purpose of the embodiments herein, an "application" may refer to one or more processes, threads, programs, client modules, server modules, or any other software that executes on a device or group of devices. A "service" may refer to a high-level capability provided by multiple applications executing on one or more devices working in conjunction with one another. For example, a high-level web service may involve multiple web application server threads executing on one device and accessing information from a database application that executes on another device.

<FIG> provides a logical depiction of how configuration items can be discovered, as well as how information related to discovered configuration items can be stored. For sake of simplicity, remote network management platform <NUM>, third-party networks <NUM>, and Internet <NUM> are not shown.

In <FIG>, CMDB <NUM> and task list <NUM> are stored within computational instance <NUM>. Computational instance <NUM> may transmit discovery commands to proxy servers <NUM>. In response, proxy servers <NUM> may transmit probes to various devices, applications, and services in managed network <NUM>. These devices, applications, and services may transmit responses to proxy servers <NUM>, and proxy servers <NUM> may then provide information regarding discovered configuration items to CMDB <NUM> for storage therein. Configuration items stored in CMDB <NUM> represent the environment of managed network <NUM>.

Task list <NUM> represents a list of activities that proxy servers <NUM> are to perform on behalf of computational instance <NUM>. As discovery takes place, task list <NUM> is populated. Proxy servers <NUM> repeatedly query task list <NUM>, obtain the next task therein, and perform this task until task list <NUM> is empty or another stopping condition has been reached.

To facilitate discovery, proxy servers <NUM> may be configured with information regarding one or more subnets in managed network <NUM> that are reachable by way of proxy servers <NUM>. For instance, proxy servers <NUM> may be given the IP address range <NUM>. <NUM>/<NUM> as a subnet. Then, computational instance <NUM> may store this information in CMDB <NUM> and place tasks in task list <NUM> for discovery of devices at each of these addresses.

<FIG> also depicts devices, applications, and services in managed network <NUM> as configuration items <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. As noted above, these configuration items represent a set of physical and/or virtual devices (e.g., client devices, server devices, routers, or virtual machines), applications executing thereon (e.g., web servers, email servers, databases, or storage arrays), relationships therebetween, as well as services that involve multiple individual configuration items.

Placing the tasks in task list <NUM> may trigger or otherwise cause proxy servers <NUM> to begin discovery. Alternatively or additionally, discovery may be manually triggered or automatically triggered based on triggering events (e.g., discovery may automatically begin once per day at a particular time).

In general, discovery may proceed in four logical phases: scanning, classification, identification, and exploration. Each phase of discovery involves various types of probe messages being transmitted by proxy servers <NUM> to one or more devices in managed network <NUM>. The responses to these probes may be received and processed by proxy servers <NUM>, and representations thereof may be transmitted to CMDB <NUM>. Thus, each phase can result in more configuration items being discovered and stored in CMDB <NUM>.

In the scanning phase, proxy servers <NUM> may probe each IP address in the specified range of IP addresses for open Transmission Control Protocol (TCP) and/or User Datagram Protocol (UDP) ports to determine the general type of device. The presence of such open ports at an IP address may indicate that a particular application is operating on the device that is assigned the IP address, which in turn may identify the operating system used by the device. For example, if TCP port <NUM> is open, then the device is likely executing a WINDOWS® operating system. Similarly, if TCP port <NUM> is open, then the device is likely executing a UNIX® operating system, such as LINUX®. If UDP port <NUM> is open, then the device may be able to be further identified through the Simple Network Management Protocol (SNMP). Other possibilities exist. Once the presence of a device at a particular IP address and its open ports have been discovered, these configuration items are saved in CMDB <NUM>.

In the classification phase, proxy servers <NUM> may further probe each discovered device to determine the version of its operating system. The probes used for a particular device are based on information gathered about the devices during the scanning phase. For example, if a device is found with TCP port <NUM> open, a set of UNIX®-specific probes may be used. Likewise, if a device is found with TCP port <NUM> open, a set of WINDOWS®-specific probes may be used. For either case, an appropriate set of tasks may be placed in task list <NUM> for proxy servers <NUM> to carry out. These tasks may result in proxy servers <NUM> logging on, or otherwise accessing information from the particular device. For instance, if TCP port <NUM> is open, proxy servers <NUM> may be instructed to initiate a Secure Shell (SSH) connection to the particular device and obtain information about the operating system thereon from particular locations in the file system. Based on this information, the operating system may be determined. As an example, a UNIX® device with TCP port <NUM> open may be classified as AIX®, HPUX, LINUX®, MACOS®, or SOLARIS®. This classification information may be stored as one or more configuration items in CMDB <NUM>.

In the identification phase, proxy servers <NUM> may determine specific details about a classified device. The probes used during this phase may be based on information gathered about the particular devices during the classification phase. For example, if a device was classified as LINUX®, a set of LINUX®-specific probes may be used. Likewise, if a device was classified as WINDOWS® <NUM>, as a set of WINDOWS®-<NUM>-specific probes may be used. As was the case for the classification phase, an appropriate set of tasks may be placed in task list <NUM> for proxy servers <NUM> to carry out. These tasks may result in proxy servers <NUM> reading information from the particular device, such as basic input / output system (BIOS) information, serial numbers, network interface information, media access control address(es) assigned to these network interface(s), IP address(es) used by the particular device and so on. This identification information may be stored as one or more configuration items in CMDB <NUM>.

In the exploration phase, proxy servers <NUM> may determine further details about the operational state of a classified device. The probes used during this phase may be based on information gathered about the particular devices during the classification phase and/or the identification phase. Again, an appropriate set of tasks may be placed in task list <NUM> for proxy servers <NUM> to carry out. These tasks may result in proxy servers <NUM> reading additional information from the particular device, such as processor information, memory information, lists of running processes (applications), and so on. Once more, the discovered information may be stored as one or more configuration items in CMDB <NUM>.

Running discovery on a network device, such as a router, may utilize SNMP. Instead of or in addition to determining a list of running processes or other application-related information, discovery may determine additional subnets known to the router and the operational state of the router's network interfaces (e.g., active, inactive, queue length, number of packets dropped, etc.). The IP addresses of the additional subnets may be candidates for further discovery procedures. Thus, discovery may progress iteratively or recursively.

Once discovery completes, a snapshot representation of each discovered device, application, and service is available in CMDB <NUM>. For example, after discovery, operating system version, hardware configuration and network configuration details for client devices, server devices, and routers in managed network <NUM>, as well as applications executing thereon, may be stored. This collected information may be presented to a user in various ways to allow the user to view the hardware composition and operational status of devices, as well as the characteristics of services that span multiple devices and applications.

Furthermore, CMDB <NUM> may include entries regarding dependencies and relationships between configuration items. More specifically, an application that is executing on a particular server device, as well as the services that rely on this application, may be represented as such in CMDB <NUM>. For instance, suppose that a database application is executing on a server device, and that this database application is used by a new employee onboarding service as well as a payroll service. Thus, if the server device is taken out of operation for maintenance, it is clear that the employee onboarding service and payroll service will be impacted. Likewise, the dependencies and relationships between configuration items may be able to represent the services impacted when a particular router fails.

In general, dependencies and relationships between configuration items may be displayed on a web-based interface and represented in a hierarchical fashion. Thus, adding, changing, or removing such dependencies and relationships may be accomplished by way of this interface.

Furthermore, users from managed network <NUM> may develop workflows that allow certain coordinated activities to take place across multiple discovered devices. For instance, an IT workflow might allow the user to change the common administrator password to all discovered LINUX® devices in a single operation.

In order for discovery to take place in the manner described above, proxy servers <NUM>, CMDB <NUM>, and/or one or more credential stores may be configured with credentials for one or more of the devices to be discovered. Credentials may include any type of information needed in order to access the devices. These may include userid / password pairs, certificates, and so on. In some embodiments, these credentials may be stored in encrypted fields of CMDB <NUM>. Proxy servers <NUM> may contain the decryption key for the credentials so that proxy servers <NUM> can use these credentials to log on to or otherwise access devices being discovered.

The discovery process is depicted as a flow chart in <FIG>. At block <NUM>, the task list in the computational instance is populated, for instance, with a range of IP addresses. At block <NUM>, the scanning phase takes place. Thus, the proxy servers probe the IP addresses for devices using these IP addresses, and attempt to determine the operating systems that are executing on these devices. At block <NUM>, the classification phase takes place. The proxy servers attempt to determine the operating system version of the discovered devices. At block <NUM>, the identification phase takes place. The proxy servers attempt to determine the hardware and/or software configuration of the discovered devices. At block <NUM>, the exploration phase takes place. The proxy servers attempt to determine the operational state and applications executing on the discovered devices. At block <NUM>, further editing of the configuration items representing the discovered devices and applications may take place. This editing may be automated and/or manual in nature.

The blocks represented in <FIG> are for purpose of example. Discovery may be a highly configurable procedure that can have more or fewer phases, and the operations of each phase may vary. In some cases, one or more phases may be customized, or may otherwise deviate from the exemplary descriptions above.

A CMDB, such as CMDB <NUM>, provides a repository of configuration items, and when properly provisioned, can take on a key role in higher-layer applications deployed within or involving a computational instance. These applications may relate to enterprise IT service management, operations management, asset management, configuration management, compliance, and so on.

For example, an IT service management application may use information in the CMDB to determine applications and services that may be impacted by a component (e.g., a server device) that has malfunctioned, crashed, or is heavily loaded. Likewise, an asset management application may use information in the CMDB to determine which hardware and/or software components are being used to support particular enterprise applications. As a consequence of the importance of the CMDB, it is desirable for the information stored therein to be accurate, consistent, and up to date.

A CMDB may be populated in various ways. As discussed above, a discovery procedure may automatically store information related to configuration items in the CMDB. However, a CMDB can also be populated, as a whole or in part, by manual entry, configuration files, and third-party data sources. Given that multiple data sources may be able to update the CMDB at any time, it is possible that one data source may overwrite entries of another data source. Also, two data sources may each create slightly different entries for the same configuration item, resulting in a CMDB containing duplicate data. When either of these occurrences takes place, they can cause the health and utility of the CMDB to be reduced.

In order to mitigate this situation, these data sources might not write configuration items directly to the CMDB. Instead, they may write to an identification and reconciliation application programming interface (API). This API may use a set of configurable identification rules that can be used to uniquely identify configuration items and determine whether and how they are written to the CMDB.

In general, an identification rule specifies a set of configuration item attributes that can be used for this unique identification. Identification rules may also have priorities so that rules with higher priorities are considered before rules with lower priorities. Additionally, a rule may be independent, in that the rule identifies configuration items independently of other configuration items. Alternatively, the rule may be dependent, in that the rule first uses a metadata rule to identify a dependent configuration item.

Metadata rules describe which other configuration items are contained within a particular configuration item, or the host on which a particular configuration item is deployed. For example, a network directory service configuration item may contain a domain controller configuration item, while a web server application configuration item may be hosted on a server device configuration item.

A goal of each identification rule is to use a combination of attributes that can unambiguously distinguish a configuration item from all other configuration items, and is expected not to change during the lifetime of the configuration item. Some possible attributes for an example server device may include serial number, location, operating system, operating system version, memory capacity, and so on. If a rule specifies attributes that do not uniquely identify the configuration item, then multiple components may be represented as the same configuration item in the CMDB. Also, if a rule specifies attributes that change for a particular configuration item, duplicate configuration items may be created.

Thus, when a data source provides information regarding a configuration item to the identification and reconciliation API, the API may attempt to match the information with one or more rules. If a match is found, the configuration item is written to the CMDB. If a match is not found, the configuration item may be held for further analysis.

Configuration item reconciliation procedures may be used to ensure that only authoritative data sources are allowed to overwrite configuration item data in the CMDB. This reconciliation may also be rules-based. For instance, a reconciliation rule may specify that a particular data source is authoritative for a particular configuration item type and set of attributes. Then, the identification and reconciliation API will only permit this authoritative data source to write to the particular configuration item, and writes from unauthorized data sources may be prevented. Thus, the authorized data source becomes the single source of truth regarding the particular configuration item. In some cases, an unauthorized data source may be allowed to write to a configuration item if it is creating the configuration item or the attributes to which it is writing are empty.

Additionally, multiple data sources may be authoritative for the same configuration item or attributes thereof. To avoid ambiguities, these data sources may be assigned precedences that are taken into account during the writing of configuration items. For example, a secondary authorized data source may be able to write to a configuration item's attribute until a primary authorized data source writes to this attribute. Afterward, further writes to the attribute by the secondary authorized data source may be prevented.

In some cases, duplicate configuration items may be automatically detected by reconciliation procedures or in another fashion. These configuration items may be flagged for manual de-duplication.

In line with the discussion above, a computational instance, such as computational instance <NUM>, can store a database that contains a definition of a service model. By way of example, <FIG> is a schematic drawing illustrating an example structure of a service model <NUM>. Service model <NUM> can represent CIs disposed within a managed network, such as a set of computing devices of a managed network and a set of software applications configured to execute on the set of computing devices. In addition, service model <NUM> may be used to model relationships and connections between CIs as reflected in CMDB <NUM>.

As shown in <FIG>, service model <NUM> includes one or more service containers <NUM> that contain information about various service environments <NUM> and <NUM>. These service environments <NUM> and <NUM> enable separating a service into various environments (e.g., development, production, testing, etc.). For example, service environment <NUM> may correspond to a first environment having first computing resources, and service environment <NUM> may correspond to a second environment having second computing resources.

Each of service environments <NUM> and <NUM> may include one or more service layers <NUM>. Service layers <NUM> may include information and/or actions for the service corresponding to service container <NUM>. For example, service layers <NUM> may include an entry points layer that contains data specifying the entry points for the service. Service layers <NUM> may also include a matching layer that contains data related to a topology for CIs associated with the service. Further, service layers <NUM> may include an impact layer that stores data related to event management operations, such as impact rules that are assigned to CIs associated with the service. Impact rules, which can be used for impact calculation, estimate the magnitude or severity of an outage based on one or more affected CIs. For example, an impact rule can define how impact applies to parent or child entities that are part of a business service, or how cluster members affect an overall cluster status based on a percentage or number of cluster members.

In some embodiments, service layers <NUM> may be arranged hierarchically and have dependencies between one another. For instance, each individual service layer may depend on the service layer(s) below the individual service layer. As one example, service layer <NUM> may depend on service layer <NUM>, which in turn may depend on service layer <NUM>. CIs of an environment can be assigned to one of service layers <NUM>.

The topology of a service model can include a graph or service map that represents relationships between CIs associated with a service. For instance, the topology may be a visual representation that depicts particular applications operating on particular computing devices in the managed network as nodes in a graph. The edges of the graph may represent physical and/or logical network connectivity between these nodes. This visual representation allows users to rapidly determine the impact of a problematic CI on the rest of the service. For instance, rather than viewing, in isolation, the properties of a database application, this application can be represented as having connections to other applications and the computing devices that rely upon or support the application. Thus, if the database is exhibiting a problem (e.g., running out of storage capacity), the impacted service(s) can be efficiently determined.

<FIG> provides an example service map including applications and computing devices that make up an email service that supports redundancy and high-availability. This service map may be generated for display on the screen of a computing device. As noted above, the nodes in the service map represent applications operating on computing devices. These nodes may take the form of icons related to the respective functions of the applications or computing devices.

The entry point to the email service, as designated by the large downward-pointing arrow, may be load balancer <NUM>. Load balancer <NUM> may be represented with a gear icon, and may operate on a device with host name maillb. This host name, as well as other host names herein, may be a partially-qualified or fully-qualified domain name in accordance with DNS domain syntax.

Load balancer <NUM> may distribute incoming requests across mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> operating on mail server devices msrv1. com, msrv2. com, msrv3. com, and msrv4. com, respectively. These mail server devices may be represented by globe icons on the service map. Connectivity between load balancer <NUM> and each of mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> is represented by respective edges.

Mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> may, for instance, respond to incoming requests for the contents of a user's mail folder, for the content of an individual email message, to move an email message from one folder to another, or to delete an email message. Mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> may also receive and process incoming emails for storage by the email service. Other email operations may be supported by mailbox applications <NUM>, <NUM>, <NUM>, and <NUM>. For sake of example, it may be assumed that mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> perform essentially identical operations, and any one of these applications may be used to respond to any particular request.

The actual contents of users' email accounts, including email messages, folder arrangements, and other settings, may be stored in one or more of mail database applications <NUM>, <NUM>, and <NUM>. These applications may operate on database server devices db0. com, and mdbx. com, which are represented by database icons on the network map. Connectivity between mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> and each of mail database applications <NUM>, <NUM>, and <NUM> also is represented by respective edges.

Mailbox applications <NUM>, <NUM>, <NUM>, and <NUM> may retrieve requested data from mail database applications <NUM>, <NUM>, and <NUM>, and may also write data to mail database applications <NUM>, <NUM>, and <NUM>. The data stored by mail database applications <NUM>, <NUM>, and <NUM> may be replicated across all of the database server devices.

The arrangement of <FIG> may vary. For example, more or fewer load balancers, mailbox applications, mail database applications, as well as their associated devices, may be present. Furthermore, additional devices may be included, such as storage devices, routers, switches, and so on. Additionally, while <FIG> is focused on an example email service, similar network maps may be generated and displayed for other types of services, such as web services, remote access services, automatic backup services, content delivery services, and so on.

Additionally, nodes representing devices of the same type or operating the same application or type of application may be placed at the same horizontal level, as in <FIG>. Nodes representing the entry point of the represented service may be placed at the top of the map, and the vertical arrangement of nodes may roughly correspond to the order in which the nodes become involved in carrying out operations of the service. Nonetheless, as the number of nodes and connections grows, such arrangements may vary for purposes of making presentation of the network map readable.

Synchronization between a CMDB, such as CMDB <NUM>, and a service model, such as service model <NUM>, can be maintained using a re-computation process. For instance, following a change in the CMDB, the re-computation process can be used to recalculate the structure or properties of the service model.

The change in the CMDB may include either a change to a CI attribute or a change to the topology of the service model (e.g., relations removed, relations, added, etc.). For a change affecting a given CI, the re-computation process can involve updating the information for the given CI in the service model, and also re-building the topology of the service model based on relations between the given CI and other CIs of the CMDB. Re-building the topology can involve identifying an entry point of a service to which the given CI relates, tracing the entry point to the given CI based on a set of relations between the given CI and the entry point, and resolving the set of relations into a graph.

Unfortunately, however, this re-computation process can be wasteful in terms of consumption of memory and processing resources. For instance, for a CI change that does not affect a topology of the service model, recalculating the structure of the service model may be unnecessary. To address this and potentially other issues, multiple re-computation modes are provided, from which an appropriate re-computation mode can be selected and carried out based on a type of change that is made to a CI.

By way of example, when a change is made to a CI record of a CMDB, a server device adds a change record corresponding to the change to a change record table. The change record specifies a change type that is indicative of whether the change affects a topology of service model. The server device uses the change type specified in the change record as a basis for selecting a service model re-computation mode from among a plurality of service model re-computation modes, and re-compute a service layer of the service model in accordance with the selected service model re-computation mode.

For instance, if a CI change does not affect a topology of the service model, then, based on the CI change not affecting the topology, a fast re-computation mode is selected rather than a full re-computation mode. In accordance with the fast re-computation mode, a CI record as changed can be merged into the definition of the service model without traversing the database in search of changes to the topology of the service model. On other hand, for a CI change that does affect a topology of the service model, the full re-computation mode is selected.

In one example, when a full re-computation mode is selected, re-computing the service model can involve traversing the database based on entry points of the service so as to re-map the topology of a service layer. For instance, the entry points of the service can be provided as input to a topology builder. A CMDB walker of the topology builder can use the entry points as a starting point, and then "walk" through CI records of the CMDB based on configuration data for the entry points that specifies relations between the entry points and other CIs of the service environment. As the CDMB walker traverses the CMDB, the topology builder can discover the CIs that the entry points are related to, discover other CIs in the environment that those CIs are related to, and so forth. After walking through CI records of the CMDB for CIs of the service environment, the topology builder can then resolve the entry points, CIs, and relations into a graph of CIs, with the graph indicating relationships between the CIs. The resulting graph, and its CIs and relations, can then be incorporated into the service model.

<FIG> depicts an example change record table <NUM>. As noted above, a server device can add change records to change record table <NUM> when changes are made to CI records of a CMDB. As shown in <FIG>, each change record can specify a change type, service layer, service environment, CI identifier (ID), and status.

The change type can be indicative of whether the change affects a topology of the service model. In one example, the change type can be selected from one of four possible change types: topology change, CI change, impact rule change, and special CI change. The change type of topology change can be used for changes that affect the topology of the service model. For instance, topology change can be used for changes where a relation between a first CI and a second CI is added, removed, or modified.

The change types of CI change, impact rule change, and special CI change can be used for changes that do not affect a topology of the service model. For changes that do not affect the topology but do modify an impact rule assigned to a CI, the change type of impact rule change can be used. For changes that do not affect the topology but do modify one or more particular fields of a CI record (e.g., a name field), the change type of special CI change can be used. For changes that do not affect the topology, do not modify impact rules, and do not modify one or more of the particular fields, the change type of CI change can be used.

The service layer and service environment of a change record can reference a respective service layer and service environment that a CI is assigned to, while the CI ID can be an identifier of the CI.

Further, the status field of a change record can be used by a server device to manage re-computation of the service model. For example, the server device can re-compute service environments of the service model one-by-one. When the server device determines that change record table <NUM> includes at least one change record corresponding to a service environment, the server device can flag the service environment for re-computation. Further, the server device can then search through change record table for any service layers in that service environment having a status of "WAITING" and change the status to "IN_PROCESS. " After a service layer is re-computed in accordance with the selected service model re-computation mode, the server device can change the status field for the service layer in change record table <NUM> to "PROCESSED".

When the server device re-computes a service environment, the server device can re-compute the service layers of the service environment one-by-one based on the change types of the service layers. By way of example, for each service layer, a service model re-computation mode can be selected based on the change type(s) for the change records corresponding to the service layer. For instance, for a service layer having a change record with change type of topology change, the server device can select a full re-computation mode for the service layer. When multiple change records having different change types correspond to a single service layer, the re-computation mode for the service layer can be determined based on the different change types.

<FIG> is a flow chart depicting example operations that can be carried out to select a service model re-computation mode for a service layer. As shown in <FIG>, at block <NUM>, a server device can determine, with reference to a change record table, whether the service layer includes any change records having a type of CI change. Based on identifying at least one change record for the service layer having a change type of CI change, the server device can designate the service model re-computation mode as CI_CHANGES. This designation may be subsequently overridden, depending on the outcome of operations performed at blocks <NUM>, <NUM>, and <NUM>.

At block <NUM>, the server device can then further determine whether the service layer includes any change records having a change type of impact rule change. Based on identifying at least one change record for the service layer having a change type of impact rule change, the server device can designate the service model re-computation mode as IMPACT_RULE_CHANGES. This designation may be subsequently overridden, depending on the outcome of operations performed at blocks <NUM> and <NUM>.

At block <NUM>, the server device can then further determine whether the service layer includes any change records having a change type of special CI change. Based on identifying at least one change record for the service layer having a change type of special CI changes, the server device can designate the service model re-computation mode as SPECIAL_CI_CHANGES. This designation may also be subsequently overridden, depending on the outcome of the operation performed at block <NUM>.

At block <NUM>, the server device can then determine whether the service layer includes any change records having a change type of topology change. Based on identifying at least one change record for the service layer having a change type of topology change, the server device can designate the service model re-computation mode as MIXED. Therefore, the service model re-computation mode that is selected for the service layer is the mode designated after the operations at blocks <NUM>, <NUM>, <NUM>, and <NUM> have been carried out.

The CI_CHANGES mode, the IMPACT_RULE_CHANGES mode, and the SPECIAL_CI_CHANGES mode can be fast re-computation modes. As noted above, as part of a fast-recomputation mode, a CI record as changed can be merged into the definition of the service model without traversing a CMDB in search of changes to the topology of the service model. The operations carried out in accordance with these three fast re-computation modes may, however, vary based on whether the mode is CI_CHANGES, IMPACT_RULE_CHANGES, or SPECIAL_CI_CHANGES. For instance, re-computing the service layer in accordance with the IMPACT_RULE_CHANGES mode can include providing an impact-rule-change notification to an event management service. As another example, re-computing the service layer in accordance with the SPECIAL_CI_CHANGES mode can include providing a name-change notification to the event management service.

The MIXED mode can be a full re-computation mode. Hence, re-computing the service layer in accordance with the MIXED mode can include traversing a CMDB based on entry points of a service so as to re-map the topology of the service layer.

In some examples, the server device can select a service model re-computation mode for a service layer of a service environment based on the service model re-computation mode that is selected for a previous layer of the service environment. For instance, with reference to service environment <NUM> of <FIG>, the server device can select a service model re-computation layer for service layer <NUM> based on the service model re-computation mode that is selected for service layer <NUM>. Similarly, the server device can select a service model re-computation layer for service layer <NUM> based on the service model re-computation mode that is selected for service layer <NUM>.

In some cases, it may be desirable to select the service model re-computation mode for a service layer based on the service model re-computation mode of a previous layer. For instance, a full re-computation mode may have been selected for a previous service layer due to the presence of a topology change for a CI of the previous service layer. Since the topology change could affect other service layers, selecting the full re-computation mode for other service layers of the service environment can help to make sure the service model is updated to account for any topology changes within the service environment.

<FIG> is a flow chart depicting example operations that can be carried out to select a service model re-computation mode for a service layer based on the service model re-computation mode selected for a previous service layer. Within <FIG>, current mode refers to the current service model re-computation mode that is selected for a service layer based on change types of change records for the service layer. Further, previous mode refers to the service model re-computation mode that is selected for the previous service layer (e.g., a service layer that is immediately below the service layer hierarchically). The operations of <FIG> could be carried out as part of a process that receives as input a current mode for a service layer and a previous mode for the previous service layer and outputs (i.e., returns) either the current mode or the previous mode as a service model re-computation mode for the service layer.

As shown in <FIG>, at block <NUM>, the server device determines whether the current mode is UNKNOWN. The current mode could, for instance, be unknown if there are not any change records corresponding to the service layer in the change record table. In some instances, when the server device re-computes a service environment, the server device may re-compute all service layers of that service environment. Hence, it is possible that the change record table might not include any change records corresponding to the service layer in which case the current mode would be UNKNOWN. Based on determining that the current mode is UKNOWN, the server device can then, at block <NUM>, determine whether the previous mode exists. If the previous mode exists, the previous mode is returned. Whereas, if the previous mode does not exist, the current mode (i.e., UNKNOWN) is returned. The UKNOWN mode is a full re-computation mode.

Based on determining that the current mode is not UNKNOWN, at block <NUM>, the server device determines whether the current mode is CI_CHANGES. Based on determining that the current mode is CI_CHANGES, the server device can then, at block <NUM>, determine whether the previous mode exists. If the previous mode exists, the previous mode is returned. Whereas, if the previous mode does not exist, the current mode (i.e., CI_CHANGES) is returned.

Based on determining that the current mode is not CI_CHANGES, at block <NUM>, the server device determines whether the current mode is IMPACT_RULE_CHANGES. Based on determining that the current mode is IMPACT_RULE_CHANGES, the server device can then, at block <NUM>, determine whether the previous mode exists and is not equal to CI_CHANGES. If the previous mode exists and is not equal to CI_CHANGES, the previous mode is returned. Whereas, if the previous mode does not exist or is equal to CI_CHANGES, the current mode (i.e., IMPACT_RULE_CHANGES) is returned. In other words, based on the determination at block <NUM>, the returned mode is either IMPACT_RULE_CHANGES, SPECIAL_CI_CHANGES, or MIXED. This can ensure that, if the previous service layer or the current service layer includes a special CI change or a topology change, the re-computation mode for the service layer will be determined based on the previous mode, so that the service layer can be re-computed as appropriate to account for the special CI change or the topology change.

Based on determining that the current mode is not IMPACT_RULES_CHANGES, at block <NUM>, the server device determines whether the current mode is SPECIAL_CI_CHANGES. Based on determining that the current mode is SPECIAL_CI_CHANGES, the server device can then, at block <NUM>, determine whether the previous mode exists and is not equal to CI_CHANGES and is also not equal to IMPACT_RULE_CHANGES. If the previous mode exists and is not equal to CI_CHANGES and is also not equal to IMPACT_RULE_CHANGES, the previous mode is returned. Whereas, if the previous mode does not exist or is equal to CI_CHANGES or is equal to IMPACT_RULE_CHANGES, the current mode (i.e., SPECIAL_CI_CHANGES) is returned.

Based on determining that the current mode is not SPECIAL_CI_CHANGES, at block <NUM>, the server device determines whether the current mode is MIXED. Based on determining that the current mode is MIXED, the current mode is returned. As noted above, the MIXED mode is a full re-computation mode.

<FIG> is a flow chart illustrating an example embodiment. The process illustrated by <FIG> may be carried out by a computing device, such as computing device <NUM>, and/or a cluster of computing devices, such as server cluster <NUM>. However, the process can be carried out by other types of devices or device subsystems. For example, the process could be carried out by a portable computer, such as a laptop or a tablet device.

The embodiments of <FIG> may be combined with features, aspects, and/or implementations of any of the previous figures or otherwise described herein.

Block <NUM> of <FIG> involves maintaining, by one or more computing devices of a computational instance, a database that contains a plurality of CI records corresponding to a set of computing devices within a managed network, a set of software applications configured to execute on the set of computing devices, and a network-based service that is provided by execution of the set of software applications. The managed network may be associated with the computational instance. In addition, the database contains a definition of a service model that represents the set of computing devices, the set of software applications, and relationships therebetween that facilitate providing the network-based service. Further, the service model includes a service environment having multiple service layers that are hierarchically-arranged.

Block <NUM> of <FIG> involves receiving, by the one or more computing devices from the managed network, an indication of a change to a CI record of the plurality of CI records.

Block <NUM> of <FIG> involves storing, in the database, the CI record as changed.

Block <NUM> of <FIG> involves adding, by the one or more computing devices to a change record table stored within the database, a change record corresponding to the change to the CI record. The change record (i) references the CI record and a service layer of the multiple service layers, and (ii) specifies a change type that is indicative of whether the change affects a topology of the service model.

Block <NUM> of <FIG> involves selecting, by the one or more computing devices based on the change type, for the service layer a service model re-computation mode from among a plurality of service model re-computation modes.

Block <NUM> of <FIG> involves re-computing, by the one or more computing devices, the service layer of the service environment in accordance with the service model re-computation mode.

In some cases, the change type indicates that the change does not affect the topology, and selecting the service model re-computation model involves selecting a fast recomputation mode rather than a full re-computation mode that consumes more memory when carried out than the fast re-computation mode. In these embodiments, re-computing the service layer of the service environment in accordance with the fast re-computation mode may involve merging the CI record as changed into the service model without traversing the database in search of changes to the topology of the service model.

Additionally, the change type may further indicate that the change is an impact rule change, in which case re-computing the service layer of the service environment in accordance with the fast re-computation mode may further involve providing an impact-rule-change notification to an event management service disposed within the remote network management platform. Alternatively, the change type may further indicate that the change is a change to a name field of the CI record, in which re-computing the service layer of the service environment in accordance with the fast re-computation mode may further involve providing a name-change notification to an event management service disposed within the remote network management platform.

In some cases, the change type indicates that the change affects the topology, and selecting the service model re-computation mode involves selecting a full re-computation mode rather than a fast re-computation mode that consumes less memory when carried out than the full re-computation mode. In these embodiments, re-computing the service layer of the service environment in accordance with the full re-computation mode may involve traversing the database based on entry points of the network-based service so as to re-map the topology of the service layer. These embodiments of <FIG> may further involve (i) receiving, from the managed network, an indication of a second change to a second CI record of the plurality of CI records; (ii) adding, to the change record table, a second change record corresponding to the second change to the second CI record, wherein the second change record references the second CI record and a second service layer within the service environment and specifies a second change type that is indicative of whether the second change affects the topology; (iii) selecting for the second service layer, based on the change type and the second change type, a second service model re-computation mode from among the plurality of service model re-computation modes; and (iv) re-computing the second service layer of the service environment in accordance with the second service model re-computation mode. In these embodiments, the second change type may indicate that the second change does not affect the topology, but selecting the second service model re-computation mode may involve selecting the full re-computation mode based on the service model re-computation mode for the service layer being the full re-computation mode even though the second change does not affect the topology.

Some of the embodiments of <FIG> may further involve flagging the service environment for re-computation based on a reference to the service layer within the service environment. Additionally or alternatively, in some of the embodiments of <FIG>, re-computing the service layer of the service environment in accordance with the service model re-computation mode may involve creating a snapshot of the network-based service. The snapshot may specify a time indicative of when the re-computing is completed.

The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations can be made without departing from the scope of the claims, as will be apparent to those skilled in the art.

The above detailed description describes various features and operations of the disclosed systems, devices, and methods with reference to the accompanying figures. The example embodiments described herein and in the figures are not meant to be limiting. Other embodiments can be utilized, and other changes can be made, without departing from the scope of the claims. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations.

With respect to any or all of the message flow diagrams, scenarios, and flow charts in the figures and as discussed herein, each step, block, and/or communication can represent a processing of information and/or a transmission of information in accordance with example embodiments. In alternative embodiments, for example, operations described as steps, blocks, transmissions, communications, requests, responses, and/or messages can be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved.

A step or block that represents a processing of information can correspond to circuitry that can be configured to perform the specific logical functions of a herein-described method or technique. Alternatively or additionally, a step or block that represents a processing of information can correspond to a module, a segment, or a portion of program code (including related data). The program code can include one or more instructions executable by a processor for implementing specific logical operations or actions in the method or technique. The program code and/or related data can be stored on any type of computer readable medium such as a storage device including RAM, a disk drive, a solid state drive, or another storage medium.

The computer readable medium can also include non-transitory computer readable media such as computer readable media that store data for short periods of time like register memory and processor cache. The computer readable media can further include non-transitory computer readable media that store program code and/or data for longer periods of time. Thus, the computer readable media may include secondary or persistent long term storage, like ROM, optical or magnetic disks, solid state drives, compact-disc read only memory (CD-ROM), for example. The computer readable media can also be any other volatile or non-volatile storage systems. A computer readable medium can be considered a computer readable storage medium, for example, or a tangible storage device.

Moreover, a step or block that represents one or more information transmissions can correspond to information transmissions between software and/or hardware modules in the same physical device. However, other information transmissions can be between software modules and/or hardware modules in different physical devices.

Claim 1:
A computing system disposed within a remote network management platform comprising:
a database that contains a plurality of configuration item (CI) records corresponding to a set of computing devices (<NUM>) disposed within a managed network (<NUM>), a set of software applications configured to execute on the set of computing devices (<NUM>), and a network-based service that is provided by execution of the set of software applications, wherein the managed network (<NUM>) is associated with the computational instance (<NUM>, <NUM>, <NUM>, <NUM>), wherein the database contains a definition of a service model (<NUM>) that represents the set of computing devices (<NUM>), the set of software applications, and relationships therebetween that facilitate providing the network-based service, and wherein the service model (<NUM>) includes a service environment (<NUM>, <NUM>) having multiple service layers (<NUM>) that are hierarchically-arranged within the service environment (<NUM>, <NUM>); and
one or more server devices (<NUM>) configured to:
receive, from the managed network (<NUM>), an indication of a change to a CI record of the plurality of CI records;
store, in the database, the CI record as changed;
add, to a change record table (<NUM>) stored within the database, a change record corresponding to the change to the CI record, wherein the change record: (i) references the CI record and a service layer (<NUM>) of the multiple service layers, and (ii) specifies a change type that is indicative of whether the change affects a topology of the service model (<NUM>);
based on the change type, select for the service layer (<NUM>) a service model re-computation mode from among a plurality of service model re-computation modes, wherein selecting the service model re-computation mode comprises:
in response to the change type indicating that the change does not affect the topology of the service model (<NUM>), selecting a fast re-computation mode; and
in response to the change type indicating the change does affect the topology of the service model (<NUM>), selecting a full re-computation mode; and
re-compute the service layer (<NUM>) of the service environment (<NUM>, <NUM>) in accordance with the selected service model re-computation mode.