Abstract:
Methods and apparatus to manage a dynamic deployment environment including one or more virtual machines. A disclosed example involves: (a) automatically scanning the virtual machines in the deployment environment to identify a service installed on any of the virtual machines; (b) automatically determining whether the identified service corresponds to a service monitoring rule; (c) when the service corresponds to the service monitoring rule, automatically determining whether a monitoring agent identified by the service monitoring rule is installed on the virtual machines on which the service is installed; (d) when the monitoring agent identified by the service monitoring rule is not installed on the virtual machines on which the service is installed, automatically installing the monitoring agent on the virtual machines on which the service is installed; and (e) when the monitoring agent identified by the service monitoring rule is installed on the virtual machines on which the service is installed, automatically configuring the monitoring agent to monitor the service in accordance with the service monitoring rule on the virtual machines on which the service is installed, wherein (a), (b), (c), (d) and (e) are repeatedly performed without human intervention.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent arises from a continuation of U.S. patent application Ser. No. 14/319,326, filed Jun. 30, 2014. U.S. patent application Ser. No. 14/319,326 is hereby incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    This disclosure relates generally to virtual machine computing and, more particularly, to methods and apparatus to manage monitoring agents in a virtual machine computing cloud. 
       BACKGROUND 
       [0003]    “Infrastructure-as-a-Service” (also commonly referred to as “IaaS”) generally describes a suite of technologies provided by a service provider as an integrated solution to allow for elastic creation of a virtualized, networked, and pooled computing platform (sometimes referred to as a “cloud computing platform”). Enterprises may use IaaS as a business-internal organizational cloud computing platform (sometimes referred to as a “private cloud”) that gives an application developer access to infrastructure resources, such as virtualized servers, storage, and networking resources. By providing ready access to the hardware resources required to run an application, the cloud computing platform enables developers to build, deploy, and manage the lifecycle of a web application (or any other type of networked application) at a greater scale and at a faster pace than before. 
         [0004]    Deployment tools currently in use are usually a patchwork of various software products from different vendors and/or homegrown solutions. Such tools are generally process-driven with heavy reliance on custom scripts and property files. Traditional deployment tools are also not configured for automation with cloud computing platforms that dynamically provision virtual computing resources. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a block diagram of an example system constructed in accordance with the teachings of this disclosure for automatically managing monitoring agents. 
           [0006]      FIG. 2  is a block diagram of an example virtual machine that may be analyzed by the example system of  FIG. 1  to determine whether to install and/or remove a monitoring agent to monitor the virtual machine. 
           [0007]      FIG. 3  illustrates an example interface that may be presented by the service rule definer of  FIG. 1  to facilitate creation and/or management of a service rule. 
           [0008]      FIG. 4  is a flowchart representative of example machine readable instructions that may be executed to implement the system of  FIG. 1  to automatically install a monitoring agent on a computing unit. 
           [0009]      FIG. 5  is a flowchart representative of example machine readable instructions that may be executed to implement the system of  FIG. 1  to automatically install monitoring agents on computing units based on a multi-tiered application. 
           [0010]      FIG. 6  is a flowchart representative of example machine readable instructions that may be executed to implement the system of  FIG. 1  to automatically remove and/or reconfigure a monitoring agent when a service is removed from a computing unit. 
           [0011]      FIG. 7  is a block diagram of an example processor platform capable of executing the instructions of  FIGS. 4, 5 , and/or  6  to implement the system of  FIG. 1 . 
       
    
    
       [0012]    Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. 
       DETAILED DESCRIPTION 
       [0013]    Monitoring agents are installed on computing units (e.g., virtual machines (VM), physical machines (PM), etc.) to, for example, monitor the performance of applications. Because monitoring agents are resource intensive, virtual infrastructure administrators typically install monitoring agents on computing units running important services (e.g., web servers, application servers, database servers, application components, etc.) that need to be monitored (and typically do not install monitoring agents on other less important computing units). Currently, the virtual infrastructure administrators manually install and configure monitoring agents on the computing units with services to be monitored. Because virtual environments are dynamic, applications (e.g., multi-tiered applications) and services may be scaled out automatically (e.g., by adding additional resources, services, applications, etc.). The automatic scaling of the applications and the services may require the installation of new monitoring agent(s) across new computing units and/or may require existing monitoring agents to be reconfigured for the new services and/or applications. Additionally, as services and/or applications are moved and/or removed, monitoring agents may require reconfiguration or removal from a computing unit. 
         [0014]    To accommodate management of monitoring agents (e.g., without user intervention), in examples disclosed herein, a user (e.g., the virtual infrastructure administrator) defines service rules. The service rules may, for example, define the service(s) that require monitoring agents, the computing units and/or groups to monitor for the service(s), and/or criteria for installation (e.g., install/configure a monitoring agent for every detected instance of a service, install a monitoring agent only when a service is newly installed, etc.). The service rule may also define configuration information (e.g., IP address, installation source, credentials, etc.) relating to a monitoring agent server, service metrics to be reported to the monitoring agent server, and/or configuration properties for the monitoring agent server. 
         [0015]    A virtual infrastructure navigator (VIN), as disclosed herein, may automatically discover services executing on computing units specified by the service rules. Example systems for automatically discovering services are discussed in U.S. application Ser. No. 14/231,018 entitled “Methods and Apparatus to Automatically Configure Monitoring of a Virtual Machine,” which is incorporated by reference herein in its entirety. If a discovered service satisfies a service rule (e.g., matches the defined application and/or service, is running on a specified computing unit, and meets the specified criteria), an agent installer installs a monitoring agent on a target computing unit and/or configures the monitoring agent according to the service rule. 
         [0016]    In some examples disclosed herein, the VIN causes discovery scripts to be executed by the computing units. In some such examples, the VIN detects changes in the configuration (e.g., detects that a service has been installed, detects that a service has been removed, etc.) of the computing units. In some such examples, automatically installing a monitoring agent on a computing unit is triggered by the VIN detecting changes in the configuration of the computing unit. 
         [0017]    In some examples disclosed herein, the VIN automatically discovers the installation of multi-tiered applications. In some such examples, the VIN identifies services installed as part of the multi-tiered applications, identifies computing units corresponding to the services, and installs and/or configures monitoring agents on computing units with services that satisfy one or more service rules. 
         [0018]    In some examples disclosed herein, the VIN automatically detects when a service has been removed from a computing unit. The example VIN determines whether, according to a service rule, a monitoring agent was installed and/or configured for the service on the computing unit. In some such examples, without user intervention, the monitoring agent is reconfigured so that the monitoring agent does not attempt to monitor the removed service. Additionally or alternatively, the monitoring agent is removed from the computing unit. In this manner, unnecessary monitoring agents are removed from the deployment environment and resources are freed. 
         [0019]    Example methods and apparatus disclosed herein facilitate the automatic management of monitoring agents deployed in a deployment environment. Example methods and apparatus enable a user (e.g., a virtual infrastructure administrator, etc.) to define service rules for services and/or applications that are monitored. In some example methods and apparatus, a VIN (e.g., vCenter™ Infrastructure Navigator™, a commercially available product from VMWare®, Inc.) or similar component automatically detects services running on a computing unit (e.g., a virtual machine, a physical machine, etc.). In some examples, the automatically detected services are compared to the defined service rules. If an automatically detected service satisfies a service rule (e.g., the automatically detected service is identified in the service rule), a monitoring agent is installed and/or configured on the computing unit running the service without further intervention from the user. 
         [0020]    Example methods disclosed herein include determining if a first service is installed on computing unit (e.g., a virtual machine, a physical machine, etc.) that corresponds to a service rule, the service rule to specify a service identifier and configuration for a monitoring agent, determining if the virtual machine includes the monitoring agent, and in response to determining that the first service matches the service identifier and determining that the monitoring agent is not installed on the virtual machine, initiating installation of the monitoring agent on the virtual machine. 
         [0021]    Example apparatus disclosed herein include a service analyzer to determine whether if a virtual machine has a first service installed that corresponds to a service rule and to determine if the virtual machine has a monitoring agent corresponding to the first service, the service rule to specify a service identifier and a configuration for the monitoring agent, and an agent installer to, in response to the first service matching the service identified specified by the service rule and the monitoring agent not installed on the virtual machine, initiate installation of the monitoring agent on the virtual machine. 
         [0022]    As used herein, the term “node” or “logical node” refers to a computing unit or a cluster of computing units defined in a service rule to be monitored for a specified service. 
         [0023]    As used herein, the term “service” refers to scripted software that can be installed on a computing unit and may be reused in multiple applications. 
         [0024]    As used herein, the term “properties” refers to configuration variables used by scripts to set parameters on a script and run various configurations. For example, setting an installation path property value causes installation scripts to use the property to specify the path to use to install a monitoring agent. 
         [0025]    As used herein, the term “deployment environment” refers to a computing environment in a cloud provider. For example, separate deployment environments may be used for development, testing, staging, and/or production. A cloud provider can have one or multiple deployment environments. 
         [0026]      FIG. 1  illustrates an example system  100  for automatically managing monitoring agents  102  deployed across computing units  104  (e.g., virtual machines (VM), physical machines (PM), etc.) managed by a cloud platform provider  106  (also referred to herein as a “cloud provider”). The example system  100  includes a monitoring agent server  110  and a virtual infrastructure navigator (VIN)  112 , which may be used to automatically deploy, configure, and/or remove monitoring agents  102 . The system  100  of the illustrated example includes a discovery script repository  126  in communication with the VIN  112 . 
         [0027]    The example cloud computing platform provider  106  provisions virtual and/or physical computing resources (e.g., the computing units  104 ) to provide the deployment environments  108  in which the administrator  114  and/or developer  116  can deploy multi-tiered application(s). One particular example of a deployment environment that may be used to implement the deployment environments  112  of  FIG. 1  is vCloud DataCenter cloud computing services available from VMWare®, Inc. The example cloud computing platform provider  106  of  FIG. 1  may be used to provide multiple deployment environments  108 , for example, for development, testing, staging, and/or production of applications. The administrator  114  and/or the developer  116  may access services from the cloud computing platform provider  106 , for example, via REST (Representational State Transfer) APIs (Application Programming Interface) and/or via any other client-server communication protocol. One particular implementation of a REST API for cloud computing services is vCloud® Director API available from VMWare®, Inc. 
         [0028]    In the example illustrated in  FIG. 1 , the example deployment environment  108  includes multiple computing units  104  (e.g., virtual machines (VM) and physical machines (PM)). In the illustrated example of  FIG. 1 , services  117  (e.g., MySql server, e-mail server, etc.) are deployed across the example computing units  104  in the deployment environment  108 . In some examples, computing units  104  are added and/or removed from the deployment environment  108  by the administrator  114  and/or the developer  116 . During the use of a multi-tiered application (e.g., an application with multiple services  117  spread across one or more computing units  104 ), the multi-tiered application may be dynamically scaled up (e.g., by adding services  117  and/or computing units  104  associated with the application) or scaled down (e.g., by removing services  117  and/or computing units  104  associated with the application) to add or remove resources as required by the multi-tiered applications. 
         [0029]    In the example illustrated in  FIG. 1 , the VIN  112  includes a service analyzer  118 , a service rule definer  120 , an agent installer  122 , and a service rule database  124 . The example service rule database  124  is provided to store and/or manage service rules created, deleted, and/or modified by the example service rule definer  120 . 
         [0030]    In the example illustrated in  FIG. 1 , the administrator  114  and/or the developer  116  use the service rule definer  120  to maintain the service rule database  124  by creating, modifying, and/or deleting service rules. In the illustrated example, the service rule database  124  stores the service rules generated via the service rule definer  120 . In some examples, the service rule database  124  may be any data structure suitable for storing data, such as a relational database (e.g., a MySQL database), or an Extensible Markup Language (XML) file, etc. The example service rule definer  120  is to create, delete, and/or modify service rules used by the example service analyzer  118  to determine whether an example monitoring agent  102  is to be installed, removed, and/or configured on an example computing unit  104 . Additionally or alternatively, service rules may be imported into the service rule database  124  and may be subsequently maintained by the service rule definer  120 . 
         [0031]    In the example illustrated in  FIG. 1 , the service analyzer  118  is to monitor services deployed on computing units  104  in the example deployment environment  108 , to determine whether an example monitoring agent  102  is to be installed, removed, and/or configured on an example computing unit  104 . The example service analyzer  118  may additionally or alternatively direct the example agent installer  122  to install, remove, and/or configure an example monitoring agent  102  on an example computing unit  104 . The example service analyzer  118  selects and/or accesses discovery script(s) stored in the example discovery script repository  126 . In some examples, the discovery script repository  126  may be any data structure suitable for storing data, such as a relational database (e.g., a MySQL database), or an Extensible Markup Language (XML) file, etc. In some examples, the discovery scripts are sets of instructions to be executed by computing units  104  analyzer and/or report the configuration of the computing unit  104 . The service analyzer  118  of the illustrated example causes the discovery script(s) to be executed on the computing units  104  in the deployment environment  108  to detect changes in the configuration (e.g., detects installation of new services, detects removal of services, etc.) of the computing units  104  in the deployment environment  108 . Additionally or alternatively, the computing units  104 , from time to time, report the services installed on the computing units  104  to the VIN  112  and/or the service analyzer  118 . 
         [0032]    The example service analyzer  118  compares the service(s)  117  running on the example computing units  104  to the service rules in the service rule database  124 . If a service satisfies a service rule (e.g., meets the criteria defined in the service rule), the example service analyzer  118  directs the example agent installer  112  to initiate installation and/or configuration of an example monitoring agent  102  on example the computing unit  104  corresponding to the service. For example, a service  117  may satisfy a service rule when the service matches a service identifier included in the service rule. In some examples, the service analyzer  118  also detects when services have been removed from the computing units  104 . In some such examples, the example service analyzer  118  directs the example agent installer  122  to initiate removal of the example monitoring agent  102  from the corresponding example computing unit  104  (e.g., when no other service is being monitored by the example monitoring agent  102 ) and/or to reconfigure the example monitoring agent  102  (e.g., when another service is being monitored by the example monitoring agent  102 ). In some examples, the service analyzer  118  does not respond to detecting that a service  117  has been removed from a computing unit  104  (e.g., does not remove the example monitoring agent). 
         [0033]    In the example illustrated in  FIG. 1 , the agent installer  122  initiates installation, configuration and/or removal of a monitoring agent  102  from the computing unit  104  when directed by the service analyzer  112  according to a service rule. The example service rule identifies an initial configuration of the example monitoring agent  102  installed on the example target computing unit  104 . In some examples, the service rule defines a configuration for the agent server  110 . An example configuration includes an internet protocol (IP) address of the monitoring agent server  110 , an agent user name, an agent user password, an installation package location, a Linux platform installation directory, a Windows platform installation directory, an agent version, configuration of the agent  102  as a service, a secure connection configuration to the monitoring agent server  110 , a performance agent server port, a performance agent secure server port, a performance agent port, a unidirectional configuration (e.g., configuring either the monitoring agent  102  or the monitoring agent server  110  to initiate all communications, or configuring the monitoring agent  102  and the monitoring agent server  110  to initiate respective communications), and/or a checksum hash value. In some examples, the example service rule defines which metrics supported by the example monitoring agent  102  are to be monitored and reported to the example monitoring agent server  110 . 
         [0034]    After the example agent installer  122  of  FIG. 1  causes the installation and/or configuration of the monitoring agents  102  on the appropriate computing units  104 , the example monitoring agent server  110  of  FIG. 1  automatically registers the monitoring agents  102  on the computing units  104  (e.g., based on how the monitoring agents  102  are configured to communicate with the example monitoring agent server  110 ). Additionally, example agent installer  122  configures the computing units  104  to be monitored according to a management or monitoring policy and/or performs any other monitoring tasks associated with the service. For example, the computing units  104  may be configured to allow the monitoring agent  102  to communicate with the monitoring agent server  110  (e.g., configure permissions on the computing unit  104 , configure firewall of the computing unit  104 , etc.). 
         [0035]    In some examples, the example monitoring agent server  110  of  FIG. 1  automatically organizes the monitoring of the services. For example, the monitoring agent server  110  may group monitoring of the services  117  to enable ease of access by the administrator  114  and/or the developer  116 . In some examples, the monitoring agent server  110  may group the services  117  installed on the example computing units  104  of  FIG. 1  for access by the administrator  114  in association with a multi-tiered application. In some examples, the monitoring agent server  110  may group monitoring agents  102  on the example computing units  104  that are associated with email server services. In such an example, the administrator  116  may then access or view performance information monitored by the monitoring agents  102  for the email servers by selecting an email server group in a monitoring agent management interface (e.g., vCenter™ Hyperic® available from VMWare®, Inc.). In some examples, the monitoring agent management interface may be accessed via the monitoring agent server  110 . 
         [0036]      FIG. 2  is a block diagram of an example implementation of a virtual machine (VM)  200  executing within the development environment  108  of  FIG. 1 . The example VM  200  is one of the computing units  104  that is virtualized on physical resources  202  (e.g., processor(s), memory, storage, peripheral devices, network access, etc.) provided by the example development environment  108 . In the illustrated example the physical resources  202  are managed by a virtual machine manager (VMM)  204  of  FIG. 2 . In the illustrated example, the VMM  204  creates virtualized hardware  206  (e.g., virtualized storage, virtualized memory, virtualized processor(s), etc.) to allow multiple VMs  200  to be instantiated in the deployment environment  108  using the same physical resources  202 . In some examples, the VMM  204  manages the physical resources  202  (e.g., creates the virtualized hardware  206 ) based on polices implemented by the administrator  114  ( FIG. 1 ) and/or the developer  116  ( FIG. 1 ). For example, a policy may restrict access to particular locations in memory and/or storage, etc. 
         [0037]    In some examples, the VIN  112  of  FIG. 1  is provided with credentials (e.g., a user name and password of a user or administrator authorized to access the relevant portions of the VM  200 ) to access the components and/or properties of the VM  200  via communications interface  208  of the VMM  204  and/or a communications interface  210 . In some examples, the VIN  112  may issue text-based commands to the VM  200  to initiate discovery scripts and/or initiate installation of the monitoring agent  102 . In some examples, the VMM  204  and/or the VM  200  may report information about the services installed on the VM  200  to the VIN  112 . 
         [0038]    In the example illustrated in  FIG. 2 , the VM  200  executes a guest operating system (OS)  212  (e.g., a Windows operating system, a Linux operating system, etc.). In the illustrated example, the guest OS  212  executes the services  117 . Alternatively, the services  117  may be executed in a different environment of the VM  200  (e.g., the services  117  may execute natively on the VM  200 , etc.). Additionally, the example guest OS  212  executes the example monitoring agent  102  ( FIG. 1 ) installed by the agent installer  122  ( FIG. 1 ) based on the service rules to monitor services installed on the VM  200 . Alternatively, the monitoring agent  102  may be executed in a different environment of the VM  200  (e.g., the monitoring agent  102  may execute natively on the VM  200 , the monitoring agent  102  may execute on the physical resources, etc.). 
         [0039]    While an example manner of implementing the system  100  is illustrated in  FIGS. 1 and/or 2 , one or more of the elements, processes and/or devices illustrated in  FIGS. 1 and/or 2  may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further, the example monitoring agents  102 , the example computing units  104 , the example development environment  108 , the example monitoring agent server  110 , the example virtual infrastructure navigator  112 , the example service analyzer  118 , the example service rule definer  120 , the example agent installer  122 , the example service rule database  124 , the example VM  200 , and/or, more generally, the example system  100  of  FIG. 1  may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example monitoring agents  102 , the example computing units  104 , the example development environment  108 , the example monitoring agent server  110 , the example virtual infrastructure navigator  112 , the example service analyzer  118 , the example service rule definer  120 , the example agent installer  122 , the example service rule database  124 , the example VM  200 , and/or, more generally, the example system  100  of  FIG. 1  could be implemented by one or more analog or digital circuit(s), logic circuits, programmable processor(s), application specific integrated circuit(s) (ASIC(s)), programmable logic device(s) (PLD(s)) and/or field programmable logic device(s) (FPLD(s)). When reading any of the apparatus or system claims of this patent to cover a purely software and/or firmware implementation, at least one of the example monitoring agents  102 , the example computing units  104 , the example development environment  108 , the example monitoring agent server  110 , the example virtual infrastructure navigator  112 , the example service analyzer  118 , the example service rule definer  120 , the example agent installer  122 , the example VM  200 , and/or the example service rule database  124  is/are hereby expressly defined to include a tangible computer readable storage device or storage disk such as a memory, a digital versatile disk (DVD), a compact disk (CD), a Blu-ray disk, etc. storing the software and/or firmware. Further still, the example system  100  of  FIGS. 1 and/or 2  may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated in  FIGS. 1 and/or 2 , and/or may include more than one of any or all of the illustrated elements, processes and devices. 
         [0040]      FIG. 3  illustrates an example interface  300  that may be presented by the example service rule definer  120  of  FIG. 1  (e.g., to the administrator  114  and/or the developer  116  of  FIG. 1 ) to enable creation and/or management of a service rule. Example configuration information includes a service rule name  302 , an identifier  304  of application(s) and/or service(s) to be monitored, nodes  306  to monitor for the application(s) and/or the service(s) (e.g., the application(s) and/or service(s) identified by identifier  304 ), group(s)  308  to monitor for the application(s) and/or the service(s) to be monitored, criteria  310 , agent server configuration information  312  (e.g., agent server address, agent server credentials, etc.), metrics to be monitored  314 , and/or configuration properties  316 . The example configuration information  302 - 316  may be configured by the example administrator  114  and/or the example developer  116 . 
         [0041]    The example service rule name  302  is provided to facilitate the example administrator  114  and/or the example developer  116  to assign a name to the example service rule (e.g., in accordance with cloud provider administration policies). The identifier  304  is provided to enable the example administrator  114  and/or the example developer  116  to define one or more applications and/or services to be monitored. For example, a service rule may be defined for one or more services  117 , such as, MySQL 5.x servers and MySQL 4.x servers. For example, a service rule may be defined for a multi-tiered application, such as, Exchange 2010 (e.g., including agent server configuration information  312 , metrics to be monitored  314 , and/or configuration properties  316  for the services related to Exchange 2010). In the illustrated example, a node field  306  and/or a group field  308  are provided to display a selection of nodes and/or groups to define the computing units (e.g., the computing units  104  of  FIG. 1 ) to monitor for the application(s) and/or service(s) to be monitored (e.g., as identified by identifier  304 ). In some examples, the node field  306  and/or the group field  308  may be left blank and/or may not be provided on the interface  300  (e.g., any computing unit  104  in the development environment  108  and/or the cloud provider  106  ( FIG. 1 ) may be monitored for the application(s) and/or service(s) to be monitored). An example criteria field  310  may be provided to allow criteria to be specified (e.g., though text input, through selection of items on a list, etc.) For example, criteria specified in the criteria field  310  may define conditions that will cause the example service analyzer  118  of  FIG. 1  to signal the example agent installer  122  of  FIG. 1  to initiate installation, configuration and/or removal of an example monitoring agent  102 . For example, criteria may be selected in the criteria field  310  so that monitoring agents  102  are installed only in response to detecting newly installed services (e.g., services  117  of  FIG. 1 ) (as opposed to services  117  currently installed on a computing unit  104  at the time the service rule is created). In some examples, the criteria field  310  may be left blank or may not be included interface  300  (e.g., no additional criteria is required to initiate installation and/or configuration of a monitoring agent). 
         [0042]    One or more agent server configuration information fields  312  are provided to allow the example administrator  114  and/or the example developer  116  to define configuration information (e.g., an IP address of the example monitoring agent server  110  of  FIG. 1 , an agent user name, an agent user password, an installation package location, a Linux platform installation directory, a Windows platform installation directory, an agent version, configuration of the example agent  102  as a service, a secure connection configuration to the example monitoring agent server  110 , a performance agent server port, a performance agent secure server port, a performance agent port, a unidirectional configuration, and/or a checksum hash value, etc.) to install and/or configure a monitoring agent  102  (e.g., to allow the automatically installed example monitoring agent  102  to communicate with the example monitoring agent server  110  of  FIG. 1 ). In the illustrated example, one or more example metric fields  312  are provides to allow the administrator  114  and/or the developer  116  to define information to be monitored by the monitoring. In some examples, the selectable metrics in the metrics field  314  are defined according to specific services and/or applications (e.g., the services and/or the application indicated by the example identifier  304 ). In some examples, the administrator  114  and/or the developer  116  select one or more of the metrics  314  to be monitored and select an interval (e.g.,  5  minutes, default interval defined for the metric, etc.). In the illustrated example, one or more properties  316  are provided to receive a property selection. In some examples, the available property selection is determined by the identifier  304 . The example properties  316  specify parameters the example agent installer  122  uses to configure the example monitoring agent  102  according to the preferences of the administrator  114  and/or the developer  116 . 
         [0043]    Flowchart representative of example machine readable instructions for implementing the example VIN  112 , the example monitoring agent server  110  and/or the example discovery script repository  126  of  FIG. 1  are shown in  FIGS. 4, 5 , and/or  6 . In these examples, the machine readable instructions comprise a program for execution by a processor such as the processor  712  shown in the example processor platform  700  discussed below in connection with  FIG. 7 . The program may be embodied in software stored on a tangible computer readable storage medium such as a CD-ROM, a floppy disk, a hard drive, a digital versatile disk (DVD), a Blu-ray disk, or a memory associated with the processor  712 , but the entire program and/or parts thereof could alternatively be executed by a device other than the processor  712  and/or embodied in firmware or dedicated hardware. Further, although the example programs are described with reference to the flowcharts illustrated in  FIGS. 4, 5, and 6 , many other methods of implementing the example VIN  112 , the example monitoring agent server  110  and/or the example discovery script repository  126  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. 
         [0044]    As mentioned above, the example processes of  FIGS. 4, 5 , and/or  6  may be implemented using coded instructions (e.g., computer and/or machine readable instructions) stored on a tangible computer readable storage medium such as a hard disk drive, a flash memory, a read-only memory (ROM), a compact disk (CD), a digital versatile disk (DVD), a cache, a random-access memory (RAM) and/or any other storage device or storage disk in which information is stored for any duration (e.g., for extended time periods, permanently, for brief instances, for temporarily buffering, and/or for caching of the information). As used herein, the term tangible computer readable storage medium is expressly defined to include any type of computer readable storage device and/or storage disk and to exclude propagating signals and to exclude transmission media. As used herein, “tangible computer readable storage medium” and “tangible machine readable storage medium” are used interchangeably. Additionally or alternatively, the example processes of  FIGS. 4, 5 , and/or  6  may be implemented using coded instructions (e.g., computer and/or machine readable instructions) stored on a non-transitory computer and/or machine readable medium such as a hard disk drive, a flash memory, a read-only memory, a compact disk, a digital versatile disk, a cache, a random-access memory and/or any other storage device or storage disk in which information is stored for any duration (e.g., for extended time periods, permanently, for brief instances, for temporarily buffering, and/or for caching of the information). As used herein, the term non-transitory computer readable medium is expressly defined to include any type of computer readable storage device and/or storage disk and to exclude propagating signals and to exclude transmission media. As used herein, when the phrase “at least” is used as the transition term in a preamble of a claim, it is open-ended in the same manner as the term “comprising” is open ended. 
         [0045]      FIG. 4  is a flowchart representative of example machine readable instructions  400  which may be executed to implement the system  100  of  FIG. 1  to automatically install a monitoring agent (e.g., the example monitoring agent  102  of  FIGS. 1 and 2 ) on a computing unit (e.g., the example computing unit  104  of  FIG. 1  and/or the example VM  200  of  FIG. 2 ). Initially, at block  402 , the service rule definer  120  ( FIG. 1 ) defines a service rule. In some examples, the example service rule definer  120  defines a service rule after receiving input from the administrator  114  ( FIG. 1 ) and/or the developer  116  ( FIG. 1 ) via the example interface  300  ( FIG. 3 ). At block  404 , the example service analyzer  118  ( FIG. 1 ) automatically detects a service (e.g., the example service  117  of  FIG. 1 ) installed on a computing unit  104 . At block  406 , the example service analyzer  118  determines whether the example service  117  detected at block  404  satisfies the example service rule defined at block  402 . In some examples, the service  117  satisfies the service rule if the service corresponds to an identifier of service(s) to be monitored (e.g. the identifier  304  of  FIG. 3 ) defined in the service rule. Additionally or alternatively, the service  117  say satisfy the service rule if the computing unit  104  on which the service  117  is installed corresponds to a computing unit  104  specified by nodes and/or groups (e.g., specified by the example node field  306  and/or the example group field  308  of  FIG. 3 ) defined in the service rule. Additionally or alternatively, the service  117  may satisfy the service rule if the criteria (e.g., the criteria specified in the criteria field  310  of  FIG. 3 ) defined by the service rule is met (e.g., the service  117  is newly installed on the computing unit  104 , etc.). If the service  117  satisfies the service rule, program control advances to block  408 . Otherwise, if the service  117  does not satisfy the service rule, program control returns to block  404 . 
         [0046]    At block  408 , the example service analyzer  118  determines whether a monitoring agent (e.g., the example monitoring agent  102  of  FIG. 1 ) is installed on the computing unit  104  corresponding to the service  117  detected at block  404 . If a monitoring agent  102  is not installed on the computing unit  104 , program control advances to block  410 . Otherwise, program control advances to block  412 . At block  410 , the example agent installer  122  ( FIG. 1 ) initiates installation of the example monitoring agent  102  on the computing unit  104  corresponding to the service  117  detected at block  404 . In some examples, the agent installed  122  initiates the installation of the monitoring agent  102  without intervention from a user (e.g., the administrator  114  or the developer  116 , etc.). Program control then advances to block  412 . At block  412 , the agent installer  122  configures the monitoring agent  102  according to the configuration information  312 - 316  ( FIG. 3 ) defined in the service rule defined at block  402 . In some examples, the agent installer  122  configures the monitoring agent  102  without intervention from a user. Example program  400  then ends. 
         [0047]      FIG. 5  is a flowchart representative of example machine readable instructions  500  that may be executed to implement the example system  100  of  FIG. 1  to automatically (e.g., without user intervention) install monitoring agents (e.g., a monitoring agent  102  of  FIG. 1 ) on a computing unit (e.g., the example computing unit  104  of  FIG. 1 ) in response to detecting installation of a multi-tiered application. Initially, at block  502 , the example service rule definer  120  ( FIG. 1 ) defines a service rule. In some examples, the service rule definer  120  defines a service rule after receiving input from the administrator  114  ( FIG. 1 ) and/or the developer  116  ( FIG. 1 ) (e.g., through the interface  300  of  FIG. 3 ). At block  504 , the example service analyzer  118  ( FIG. 1 ) automatically (e.g., without user intervention) detects installation of a multi-tiered application on the computing unit  104  within a deployment environment (e.g., the example deployment environment  108  of  FIG. 1 ). 
         [0048]    At block  506 , the example service analyzer  118  ( FIG. 1 ) determines whether the multi-tiered application satisfies a service rule. In some examples, the multi-tiered application satisfies the service rule if the multi-tiered application corresponds to an identifier of multi-tiered application(s) to be monitored (e.g. the identifier  304  of  FIG. 3 ) defined in the service rule. Additionally or alternatively, the multi-tiered application satisfies the service rule if the computing units  104  corresponding to the multi-tiered application is installed on corresponds to a computing units  104  specified by nodes and/or groups (e.g., as specified by the node field  306  and/or the group field  308  of  FIG. 3 ) defined in the service rule. Additionally or alternatively, the multi-tiered application satisfies the service rule if the criteria (e.g., the criteria specified by the criteria field  310  of  FIG. 3 ) defined by the service rule is met (e.g., the multi-tiered application is newly installed on the computing unit  104 , etc.). If a service rule is satisfied, program control advances to block  508 . Otherwise, if a service rule is not satisfied, program control returns to block  504 . 
         [0049]    At block  508 , the service analyzer  118  detects services(s) and corresponding computing units  104  related to the installation of the multi-tiered application. In some examples, the service analyzer  118  receives an application definition (e.g., a list of the example services  117  and the example computing units  104  on which those services  117  were installed, etc.). In some examples, the service analyzer  118  causes example discovery scripts (e.g., the discovery scripts stored in the discovery script repository  126  of  FIG. 1 ) to be executed on the computing units  104  in the example deployment environment  108  to discover relationships between the services  117  related to the multi-tiered application and the computing units  104  on which the services  117  are installed. At block  510 , the service analyzer  118  selects the computing unit  104  detected at block  508 . 
         [0050]    At block  512 , the service analyzer  118  determines whether a monitoring agent (e.g., the example monitoring agent  102  of  FIGS. 1 and/or 2 ) is installed on the computing unit  104  selected at block  510 . If the monitoring agent  102  is not installed on the computing device  104 , program control advances to block  514 . Otherwise, if the monitoring agent  102  is installed on the computing device  104 , program control advances to block  516 . 
         [0051]    At block  514 , without intervention from a user (e.g., the administrator  114  or the developer  116 , etc.), the agent installer  122  ( FIG. 1 ) initiates installation of the monitoring agent  102  on the computing unit  104  selected at block  510 . Program control then advances to block  516 . 
         [0052]    At block  516 , without intervention from a user (e.g., the administrator  114  or the developer  116 , etc.), the agent installer  122  configures the monitoring agent  102  according to the configuration information  312 - 316  ( FIG. 3 ) defined in the service rule defined at block  502 . At block  518 , the service analyzer  118  determines whether there is another one of the computing units  104  detected at block  508  that requires the monitoring agent  102  to be installed and/or configured. If there is another one of the computing units  104 , program control returns to block  510 . Otherwise, the example program  500  ends. 
         [0053]      FIG. 6  is a flowchart representative of example machine readable instructions  600  which may be executed to implement the example system  100  of  FIG. 1  to automatically (e.g., without user intervention) remove and/or reconfigure a monitoring agent (e.g., the example monitoring agent  102  of  FIGS. 1 and 2 ) when a service (e.g., the example service  117  of  FIG. 1 ) is removed from a computing unit (e.g., the example computing unit  104  of  FIG. 1 ). Initially, at block  602 , the example service analyzer  118  ( FIG. 1 ) automatically detects the removal of the service  117  from the computing device  104 . At block  604 , the service analyzer  118  determines whether the service  117  detected at block  602  satisfies a service rule. In some examples, the service  117  satisfies the service rule if the service corresponds to an identifier of a service to be monitored (e.g. the identifier  304  of  FIG. 3 ) defined in the service rule. Additionally or alternatively, the service  117  satisfies the service rule if the computing unit  104  on which the service  117  was installed corresponds to the computing unit  104  specified by nodes and/or groups (e.g., the nodes  306  and/or the groups  308  of  FIG. 3 ) defined in the service rule. Additionally or alternatively, the service  117  satisfies the service rule if the criteria (e.g., the criteria specified by the criteria field  310  of  FIG. 3 ) defined by the service rule is met (e.g., the service rule allows for removal of a monitoring agent  102 , etc.). If the service  117  satisfies the service rule, program control advances to block  606 . Otherwise, if the service  117  does not satisfy the service rule, program control returns to block  602 . 
         [0054]    At block  606 , the service analyzer  118  determines whether the monitoring agent  102  installed on the computing unit  104  detected at block  602  is monitoring another service. If the monitoring agent  102  is monitoring another service, then program control advances to block  608 . Otherwise, if the monitoring agent  102  is not monitoring another service, program control advances to block  610 . 
         [0055]    At block  608 , the agent installer  122  ( FIG. 1 ) initiates reconfiguration of the monitoring agent  102  to remove configuration information (e.g., the configuration information  312 - 316 ) related to the removed service  102  according to the service rule. In some examples, the agent installer  122  initiates the reconfiguration of the monitoring agent  102  without intervention from a user (e.g., an administrator  114  and/or a developer  116  of  FIG. 1 , etc.). The example program  600  of  FIG. 6  then ends. 
         [0056]    At block  610 , the agent installer  122  initiates removal of the monitoring agent  102  from the computing unit  104  detected at block  602 . In some examples, the agent installer  122  initiates removal of the monitoring agent without intervention from the user. The example program  600  of  FIG. 6  then ends. 
         [0057]      FIG. 7  is a block diagram of an example processor platform  800  capable of executing the instructions of  FIGS. 4, 5 , and/or  6  to implement the example system  100  of  FIG. 1 . The processor platform  700  can be, for example, a server, a personal computer, or any other type of computing device. 
         [0058]    The processor platform  700  of the illustrated example includes a processor  712 . The processor  712  of the illustrated example is hardware. For example, the processor  712  can be implemented by one or more integrated circuits, logic circuits, microprocessors or controllers from any desired family or manufacturer. 
         [0059]    The processor  712  of the illustrated example includes a local memory  713  (e.g., a cache). The processor  712  of the illustrated example is in communication with a main memory including a volatile memory  714  and a non-volatile memory  716  via a bus  718 . The volatile memory  714  may be implemented by Synchronous Dynamic Random Access Memory (SDRAM), Dynamic Random Access Memory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM) and/or any other type of random access memory device. The non-volatile memory  716  may be implemented by flash memory and/or any other desired type of memory device. Access to the main memory  714 ,  716  is controlled by a memory controller. 
         [0060]    The processor platform  700  of the illustrated example also includes an interface circuit  720 . The interface circuit  720  may be implemented by any type of interface standard, such as an Ethernet interface, a universal serial bus (USB), and/or a PCI express interface. 
         [0061]    In the illustrated example, one or more input devices  722  are connected to the interface circuit  720 . The input device(s)  722  permit(s) a user to enter data and commands into the processor  812 . The input device(s) can be implemented by, for example, a keyboard, a button, a mouse, a touchscreen, a track-pad, a trackball, isopoint and/or a voice recognition system. 
         [0062]    One or more output devices  724  are also connected to the interface circuit  720  of the illustrated example. The output devices  724  can be implemented, for example, by display devices (e.g., a light emitting diode (LED), an organic light emitting diode (OLED), a liquid crystal display, a cathode ray tube display (CRT), a touchscreen, a tactile output device, a printer and/or speakers). The interface circuit  720  of the illustrated example, thus, typically includes a graphics driver card, a graphics driver chip or a graphics driver processor. 
         [0063]    The interface circuit  720  of the illustrated example also includes a communication device such as a transmitter, a receiver, a transceiver, a modem and/or network interface card to facilitate exchange of data with external machines (e.g., computing devices of any kind) via a network  726  (e.g., an Ethernet connection, a digital subscriber line (DSL), a telephone line, coaxial cable, a cellular telephone system, etc.). 
         [0064]    The processor platform  700  of the illustrated example also includes one or more mass storage devices  728  for storing software and/or data. Examples of such mass storage devices  728  include floppy disk drives, hard drive disks, compact disk drives, Blu-ray disk drives, RAID systems, and digital versatile disk (DVD) drives. 
         [0065]    The coded instructions  732  of  FIGS. 4, 5 , and/or  6  may be stored in the mass storage device  728 , in the volatile memory  714 , in the non-volatile memory  716 , and/or on a removable tangible computer readable storage medium such as a CD or DVD. 
         [0066]    From the foregoing, it will be appreciate that examples disclosed herein dynamically (e.g., without intervention from a user) scale monitoring of services executing on virtual machines implementing multi-tiered applications. In such examples, user error and oversight are minimized by detecting installation of important services so that, for example, the important services are monitored in the dynamic environment. 
         [0067]    Although examples herein disclose managing monitoring agents without user intervention, alternatively, some limited user intervention (e.g., entering credentials, starting and/or stopping the automated installation of monitoring agents, starting and/or stopping automation software, starting and/or stopping automated services, starting and/or stopping computing devices, etc.) may be used without departing from the scope of the disclosure. For example, a user may intervene to start the VIN  112  of  FIG. 1  which may then monitor the computing unit(s)  104  ( FIG. 1 ) in the deployment environment  108  ( FIG. 1 ) and install and/or remove the monitoring agent  102  ( FIG. 1 and/or 2 ) without user intervention. 
         [0068]    Although certain example methods, apparatus and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the claims of this patent.