# Patent

## Title
Managing network computing components utilizing request routing

## Abstract

Aspects of the disclosure will be described with regard to the processing of a client computing device DNS queries by a DNS processing service to determine an identifier associated with a previously instantiated hosted virtual machine instance. In one aspect, if the previously instantiated hosted virtual machine instance is instantiated, the DNS service can resolve the DNS query by transmitting network address information associated with the previously instantiated hosted virtual machine instance. In another aspect, if the previously instantiated hosted virtual machine instance is not instantiated, the DNS service can initiate a process to cause an instantiation of a hosted virtual machine instance based on the previously instantiated hosted virtual machine instance. The DNS service can then resolve the DNS query by transmitting network address information, or an alternative identifier, associated with the newly instantiated hosted virtual machine instance.

## Background
BACKGROUND
Generally described, computing devices and communication networks can be utilized to exchange information. In a common application, a computing device can request content from another computing device via a communication network. For example, a user at a personal computing device can utilize various types of software applications to request information from server computing devices via the Internet. In such embodiments, the user computing device can be referred to as a client computing device and the server computing device can be referred to as a service provider.
In some embodiments, companies and organizations operate computer networks that interconnect a number of computing devices to support operations or provide services to third parties. The computing systems can be located in a single geographic location or located in multiple, distinct geographic locations (e.g., interconnected via private or public communication networks). Specifically, data centers or data processing centers, herein generally referred to as a “data center,” may include a number of interconnected computing systems to provide computing resources to users of the data center. The data centers may be private data centers operated on behalf of an organization or public data centers operated on behalf, or for the benefit of, the general public.
In some embodiments, a client computing device may access software applications that may be provided by communication with a data center. For example, a service provider may host, or have hosted on its behalf, one or more physical computing devices in a data center that provide client computing devices with access to software application via a communication network. Additionally, the service provider can also utilize virtualization technologies to provide access to the software application. For example, the service provider can instantiate and maintain a number of virtual machine instances on the physical computing devices associated with a data center.
Service providers are generally motivated to provide requested content/services or access to requested content/services to client computing devices often with consideration of cost and customer experience. For example, service providers can associate a cost associated with providing the client computing device with access to content/service and manage instantiated virtual machine instances on the basis of cost or available resources.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrative of an environment for the management and processing of DNS queries related to hosted virtual machine instances;
FIG. 2 is a block diagram of the environment of FIG. 1 illustrating the registration of client computing devices with a network computing provider;
FIG. 3A is a block diagram of the environment of FIG. 1 illustrating the processing of a DNS query related to an initial request for instantiation of a hosted virtual machine instance by the network computing provider on behalf of a client computing device;
FIG. 3B is a block diagram of the environment of FIG. 1 illustrating an initial request for instantiation of a hosted virtual machine instance by the network computing provider on behalf of a client computing device;
FIG. 4 is a block diagram of the environment of FIG. 1 illustrating the processing of a DNS query related to a subsequent request for access of a hosted virtual machine instance by the network computing provider on behalf of a client computing device;
FIG. 5A is a block diagram of the environment of FIG. 1 illustrating the processing of a subsequent for access of a hosted virtual machine instance by the network computing provider on behalf of a client computing device;
FIG. 5B is a block diagram of the environment of FIG. 1 illustrating the processing of a subsequent for access of a hosted virtual machine instance by the network computing provider on behalf of a client computing device; and
FIG. 6 is a flow diagram of a DNS query processing routine implemented by a DNS server.



DETAILED DESCRIPTION
Generally described, the present disclosure is directed to processing DNS queries from client computing devices. Specifically, aspects of the disclosure will be described with regard to the processing of a client computing device DNS queries by a DNS processing service in which the DNS query includes an identifier associated with a previously instantiated hosted virtual machine instance. In one aspect, if the previously instantiated hosted virtual machine instance is instantiated and available to process requests, the DNS service can resolve the DNS query by transmitting network address information, or an alternative identifier, associated with the previously instantiated hosted virtual machine instance. In another aspect, if the previously instantiated hosted virtual machine instance is not instantiated and otherwise not available to process requests, the DNS service can initiate a process to cause an instantiation of a hosted virtual machine instance based on the previously instantiated hosted virtual machine instance. The DNS service can then resolve the DNS query by transmitting network address information, or an alternative identifier, associated with the newly instantiated hosted virtual machine instance.
FIG. 1 is a block diagram illustrative of an environment 100 for the management and processing of DNS queries related to hosted virtual machine instances. As illustrated in FIG. 1, the environment 100 includes a number of client computing devices 102 (generally referred to as clients) for transmitting requests to a service provider. In an illustrative embodiment, the client computing devices 102 can corresponds to a wide variety of computing devices including personal computing devices, laptop computing devices, hand-held computing devices, terminal computing devices, mobile devices, wireless devices, various electronic devices and appliances and the like. In an illustrative embodiment, the client computing devices 102 include necessary hardware and software components for establishing communications over a communication network 108, such as a wide area network or local area network. For example, the client computing devices 102 may be equipped with networking equipment and browser software applications that facilitate communications via the Internet or an intranet.
Although not illustrated in FIG. 1, each client computing device 102 utilizes some type of local DNS resolver component, such as a DNS Name server, that generates the DNS queries attributed to the client computing device. In one embodiment, the local DNS resolver component may be provide by an enterprise network to which the client computing device 102 belongs. In another embodiment, the local DNS resolver component may be provided by an Internet Service Provider (ISP) that provides the communication network connection to the client computing device 102.
With continued reference to FIG. 1, the environment 100 can further include a service provider 104 in communication with the one or more client computing devices 102 to resolve DNS queries transmitted by the client computing devices via the communication network 108. The service provider 104 illustrated in FIG. 1 corresponds to a logical association of one or more computing devices associated with a DNS service provider. Specifically, the service provider 104 can include a number of Point of Presence (“POP”) locations 110, 116, 122 that correspond to nodes on the communication network 108. Each POP 110, 116, 122 includes a DNS component 112, 118, 124 made up of a number of DNS server computing devices for resolving DNS queries from the client computers 102. Each POP 110, 116, 122 also includes resource cache components 114, 120, 126 for maintaining information related to status of various network computing components. The DNS components 112, 118, 124 may further include additional software and/or hardware components that facilitate communications including, but not limited to, load balancing or load sharing software/hardware components.
In an illustrative embodiment, the DNS component 112, 118, 124 and resource cache component 114, 120, 126 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the POPs 110, 116, 122 are illustrated in FIG. 1 as logically associated with the service provider 104, the POPs will be geographically distributed throughout the communication network 108 in a manner to best serve various demographics of client computing devices 102. Additionally, one skilled in the relevant art will appreciate that the service provider 104 can be associated with various additional computing resources, such additional computing devices for administration of content and resources, and the like.
With further continued reference to FIG. 1, the environment 100 can also include a network computing provider 106 in communication with the one or more client computing devices 102 and the service provider 104 via the communication network 108. The network computing provider 106 illustrated in FIG. 1 also corresponds to a logical association of one or more computing devices associated with a network computing and storage provider. Specifically, the network computing provider 106 can include a number of Point of Presence (“POP”) locations 128, 132, 136 that correspond to nodes on the communication network 108. Each POP 128, 132, 136 includes a network computing component (NCC) 130, 134, 138 for hosting applications, such as data streaming applications, via a number of instances of a virtual machine, generally referred to as an instance of an NCC. As will be explained in greater detail, each virtual instances hosted by an NCC is associated with an identifier that can be used by the client computing devices 102.
One skilled in the relevant art will appreciate that NCC 130, 134, 138 would include physical computing device resources and software to provide the multiple instances of a virtual machine or to dynamically cause the creation of instances of a virtual machine. Such creation can be based on a specific request, such as from a client computing device, or the NCC can initiate dynamic creation of an instance of a virtual machine on its own. Each NCC POP 128, 132, 136 may also include storage components made up of a number of storage devices. The NCCs 128, 132, 136 may further include additional software and/or hardware components that facilitate communications including, but not limited to, load balancing or load sharing software/hardware components for selecting instances of a virtual machine supporting a requested application or providing information to a DNS nameserver to facilitate request routing.
In an illustrative embodiment, NCCs 128, 132, 136 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the NCC POPs 128, 132, 136 are illustrated in FIG. 1 as logically associated with the network computing provider 106, the NCC POPs will be geographically distributed throughout the communication network 108 in a manner to best serve various demographics of client computing devices 102. Additionally, one skilled in the relevant art will appreciate that the network computing provider 106 can be associated with various additional computing resources, such additional computing devices for administration of content and resources, and the like. Even further, one skilled in the relevant art will appreciate that the components of the network computing provider 106 and components of the service provider 104 can be managed by the same or different entities.
With reference now to FIGS. 2-5B, the interaction between various components of the environment 100 of FIG. 1 will be illustrated. For purposes of the example, however, the illustration has been simplified such that many of the components utilized to facilitate communications are not shown. One skilled in the relevant art will appreciate that such components can be utilized and that additional interactions would accordingly occur without departing from the spirit and scope of the present disclosure.
Illustratively, the interaction between a customer associated with a client computing device 102 and the network computing provider 106 begins with the registration of the client computing device 102 to access computing resources made available by the network computing provider 106. In one aspect, the registration process can include the exchange of business information typical in the establishment of an account, such as the exchange of financial information, establishment of desired service levels, configuration of the desired service, and the like. In another aspect, the registration process can include the generation of information utilized by the customer, via the client computing device 102, to access the desired service, such as account identifiers, passwords and information for accessing the service provider. In addition to the registration with the network computing provider 106, the customer can also register with the service provider 104 in order to allow the service provider 104 to process DNS queries for a domain with the computing resources made available by the network computing provider 106. As will be explained in greater detail, the registration with the service provider 104 will also configure the service provider 104 to manage computing resources made available by the network computing provider 106.
In accordance with aspects of the present application, the client computing device 102 can access one or more computing devices associated with the network computing provider 106 by utilizing a resource identifier, such as uniform resource identifier (“URL”) that will be used by, which will be generally referred to as a network computing provider URL. For purposes of an illustrative example, the network computing provider URL can be characterized into two portions. The first portion identifies a domain that will used to access the network computing provider resources. Illustratively, the domain can include, but is not limited to, a domain associated with a network computing provider 106 (e.g., networkcomputingprovider.com), a domain associated with a client computing device (e.g., anydomain.com), or a domain associated with a third party (e.g., third_party_domain.com). Additionally, the first portion of the network computing provider URL can also identify one or more specific types of devices or services associated with the identified domain (e.g., services or myapplication). The first portion of the network computing provider URL can be generally referred to as a DNS portion of the network computing provider URL. Additionally, a second portion of the network computing provider URL can also include additional information utilized in the processing and request of services (“extra_information”). In a first set of illustrative examples, the network computing provider URL has the form of:
http://services.network_computing_provider.com/extra_information
http://myapplication.anydomain.com/extra_information
In accordance with an illustrative embodiment, in addition to the above information, the first portion of the network computing provider URL (e.g., the DNS portion of the network computing provider URL) can also include additional information that will be used by a DNS query processing service to manage one or more virtual machine instances associated with the client computing device transmitting the DNS query. More specifically, the DNS portion of the network computing provider URL can include one or more identifiers, or other information, that can be used to associate the DNS query to one or more-instantiated virtual machine instances by the network computing provider associated with the domain (e.g., “unique_identifier”). In one embodiment, the unique identifier can correspond to an identifier utilized by the network computing provider 106 to manage previously instantiated computing resources. In another embodiment, the unique identifier can correspond to an identifier utilized by the network computing provider 106 to instantiate computing resources. Illustratively, the unique identifier can be unique to a single customer/client computing device 102 or unique to a set of customers or client computing devices 102. In this embodiment, the DNS server can parse the unique identifier information from the DNS portion of the network computing provider URL and utilize the identifier, or identifiers, to manage virtual machine instances, as will be described. In other illustrative examples, the network computing provider URL has the form of:
http://unique_identifier.services.network_computing_provider.com/extra_information
http://unique_identifier.myapplication.mydomain.com/extra_information
In accordance with further embodiments, in addition to the above information, the first portion of the network computing provider URL can also include additional information that will be used by a DNS query processing service as part of a request routing processes to identify one or more NCC POPs that may be best suited to service requests from the client computing devices 102. More specifically, the DNS portion of the network computing provider URL can include one or more identifiers, or other information, that can be used by the DNS server to identify which NCC POP may be best suited to process the client computing device requests (e.g., “routing_information”). The additional information can be combined with the unique identifiers included in the network computing provider URL or independent of any unique identifiers included in the network computing provider URL. Illustratively, the “routing_information” can directly or indirectly identify service level information related to a desired service level, financial information related to a financial cost to be incurred as part of the request routing service, preferred routing algorithms, geographic identifiers, preferred POPs, and the like. Illustratively, the DNS server can parse the routing information from the DNS portion of the network computing provider URL and utilize the routing information as part of a request routing algorithm. In this illustrative example, the network computing provider URL has the form of:
http://routing_information.unique_identifier.services.network_computing provider.com/extra_information
http://routing_information.myapplication.mydomain.com/extra_information
Turning now to FIG. 2, an illustrative interaction for the registration of client computing devices 102 with a network computing provider 106 will be described. At (1), the client computing device 102 initiates the registration process by transmitting a request to the network computing provider 106. In one embodiment, the transmission of the request can correspond to the generation of various user interfaces to collect information from the customer associated with the client computing device 102 and transmit the collected information in accordance with an Application Protocol Interface (“API”). In other embodiments, the client computing device 102 may be configured to obtain or transmit information to the network computing provider 106 via an API without the need to generate user interfaces.
At (2), the network computing provider 106 obtains the registration request and processes the request to establish the requested account, update an existing account or otherwise establish the availability of the service for the customer. As will be explained in greater detail, the processing of the request can include the generation of the network computing provider URL, the one or more identifiers, including the unique identifier, that will be used as part of the network computing provider URL or that will be associated with the network computing provider URL. As previously described, in one embodiment, the registration process with the network computing provider 106 corresponds to the generation of a unique identifier that can be used by the network computing provider 106 to manage one or more computing resources instantiated on behalf of the customer/client computing device 102. For example, in this embodiment, the unique identifier can be used to determine whether previously instantiated virtual machine instances are available for further processing or to cause the re-instantiation of previously instantiated virtual machine instances.
In another embodiment, the registration process with the network computing provider 106 corresponds to the generation of a unique identifier that defines one or more attributes of computing devices resources that can be instantiated on behalf of the customer/client computing device 102. In this embodiment, the unique identifier can be utilized to cause the initial instantiation of the computing resources, such as one or more virtual machine instances. Illustratively, the registration process for the instantiation of computing device resources can include, but is not limited to, the specification of various hardware and software parameters for the computing device resources (physical or virtual), the configuration of various parameters (communication, security, etc.), the specification of financial cost parameters, the specification of service level agreements, and the like. Such unique identifiers may be selected from a pre-existing set of identifiers or may represent a unique configuration.
At (3), the service provider 106 transmits the network computing provider URL, unique identifiers, or a portion thereof, to the client computing device 106. The transmission can also include additional confirmation information or other information that may be used by the client computing device 102 to communicate with the service provider 106 or requests services from the network computing provider 106.
At (4), the receiving client computing device 102 then transmits a registration request with the service provider 104 to associate a network computing provider URL with one or more instance identifiers provided by the network computing provider 106. In one embodiment, the registration with the service provider 104 can correspond to a request for the service provider 104 to function as DNS query processing authority for one or more network computing provider URLs. In another embodiment, the service provider 104 may already function as the DNS query processing authority for the network computing provider URL. Accordingly, the request can corresponds to the association of the unique identifiers provides by the network computing provider 106 with the network computing provider URL. In still other embodiments, if the network computing provider URL corresponds to a domain not controlled by the client computing device 102 (e.g., serviceprovider.com), the service provider 104 may function as the DNS query processing authority for the network computing provider URL. Accordingly, the request can corresponds to the association of the unique identifiers provides by the network computing provider 106 with the network computing provider URL.
With reference to FIG. 3A, an illustrative interaction for the eventual transmission of a service request, such as request for the initiation of a hosted virtual machine instance by the network computing provider 106 on behalf of a client computing device 102. For purposes of an illustrative example, the interaction illustrated in FIG. 3A occurs at some point in time after the registration of the client computing device 102 with the network computing provider 106 and service provider 104 is complete, or otherwise, responsive to the completion of the registration process as illustrated in FIG. 2. As illustrated in FIG. 3A, the process begins at (1) with the transmission of a DNS query by a client computing device 102 to the service provider 104 to identify a network address of a particular NCC associated with the service provider 106. Illustratively, the DNS query corresponds to the network computing provider URL previously provided to the client computing device 102 during the registration process (FIG. 2).
One skilled in the relevant art will appreciate that the processing of a DNS query would begin with the identification of a DNS server authoritative to the “.” and the “com” portions of the translated URL. The issuance of DNS queries corresponding to the “.” and the “com” portions of a URL are well known and have not been illustrated. Accordingly, as illustrated in FIG. 3A, after resolving DNS queries associated with the “.” and “com” portions of the network computing provider URL, the client computing device 102 then issues a DNS query for the network computing provider URL that results in the identification of a DNS server authoritative to the portion of the network computing provider URL, in this example one of the DNS server components 112 at POP 110 associated with service provider 104
At (2), the DNS server component 112 parses the DNS query to obtain any identifier (or other information) transmitted in the DNS portion of the network computing provider URL. At (3), the DNS server component 112 at service provider 104 resolves the DNS query by identifying either a network address of an NCC component or an alternative identifier that will be utilized to identify an appropriate NCC component. Illustratively, because the DNS server component 112 receives an initial DNS query that includes unique identifier in the DNS portion of the network computing provider URL that has not been previously utilized, the DNS server component maintains information associating the unique identifier a specific network address utilized to resolve the DNS query and an identifier of the specific instance of the network computing provider 106. Accordingly, at (4), the service provider 104 transmits and receives instance identification information based on a DNS query at (5). At (6), the DNS query is resolved by transmitting the above information to the client computing device 102. One skilled in the relevant art will appreciate that the resolution of the DNS query and the maintenance of the mapping of network addresses to network computing provider 106 identifiers can occur in a different order than the order illustrated in FIG. 3A.
In an illustrative embodiment, one or more DNS components of the service provider 104 maintain tables that associate the network computing provider URL, any unique identifiers in the network computing provider URL, or combination thereof with network addresses and other identifiers associated with the NCC components of the network computing provider 106. Additionally, the DNS components of the service provider 104 can also maintain various routing information, preferences or other information that were utilized in previous request routing processes. The tables can then be utilized in processing subsequent DNS queries. In one embodiment, the table is maintained individually by one or more DNS components of the service provider 104. In other embodiments, the table (or tables) may be distributed among a select subset of the DNS components in accordance with one or more distribution schemes implemented by the service provider 104.
Table 1 illustrates an illustrative embodiment of a portion of a table utilized by a DNS component of the service provider 104:










TABLE 1






Unique




Unique Identifier
Identifier
Network Address
Routing Information







unique_identifier 1
1-xxx
123.45.678.90
None


any domain.com
5-xxx
345.78.910.11
service level


. . .
. . .
. . .
. . .


unique_identifier x1
67-xxx 
444.33.890.12
cost information









Table 2 illustrates another illustrative embodiment of a portion of a table utilized by a DNS component of the service provider 104 in which computing. As illustrated in Table 2, the first two entries in Table 2 correspond to examples in which computing device resources have not been instantiated by the network computing provider 106 on behalf of the customer/client computing device 102.











TABLE 2






Unique
Instance
Network
Routing


Unique Identifier
Identifier
Identifier
Address
Information







unique_identifier x

identifier x




yourdomain.com

Identifier




. . .
. . .

. . .
. . .


unique_identifier
67-xxx

444.33.890.12
cost


x1



information









One skilled in the art will appreciate that a table would not necessarily need to have the routing information associated with previous request routing information. Additionally, the tables may require more or less information depending on the relationship between the service provider 104 and the network computing provider 106.
Turning now to FIG. 3B, illustrating an initial request for instantiation of a hosted virtual machine instance by the network computing provider on behalf of a client computing device will be described. At (1), the client computing device 102 transmits a request to the network computing provider 106 associated with the resolved DNS query. At (2), the network computing provider 106 processes the request and instantiates one or more hosted virtual machines instances corresponding to the request. Additionally, at (3), the network computing provider 106 and client computing device 102 can begin interacting as the client computing device 102 interfaces with virtual machine instances hosted on the NCC 134.
With reference to FIG. 4, for purposes of an illustrative example, at some point, the client computing device 102 has ceased interaction with the NCC 132, at least temporarily. Depending on the time elapsed between interactions, the network computing provider 106 can either terminate a hosted instance, while maintaining information related to the state of the virtual machine instance prior to termination.
In one embodiment, to access the service again, the client computing device 102 initiates a subsequent DNS query to the service provider 104. As illustrated in FIG. 4, the process begins at (1) with the transmission of a DNS query by a client computing device 102 to the service provider 104. Illustratively, the client computing device 102 would utilize the same (or similar) network computing provider URL that was previously transmitted during the initial DNS query to the service provider 104 (FIG. 3A).
With continued reference now to FIG. 4, at (2), upon receipt of the DNS query, the DNS server parses the DNS query to obtain any identifier (or other information) associated with the previously instantiated hosted virtual machine. One skilled in the relevant art will appreciate that parsing the network computing provider URL can include parsing the “unique_identifier” information included in the DNS portion of the network computing provider URL. Alternatively, the DNS server may utilize all the DNS portion of the network computing provider URL as the “unique_identifier” portion, especially in embodiments in which no additional information is utilized for request routing is included in the DNS portion of the network computing provider URL. For example, the DNS server can utilize the identified domain (e.g., “anydomain.com”) to recall the identifier.
At (3), the DNS server can then determine whether the previously instantiated hosted virtual machine is still instantiated and available to process a subsequent request from the client computing device 102. In one embodiment, the DNS server can transmit a request to the network computing provider 106 to determine in real time or substantially real time whether the network computing provider 106 has terminated the previously instantiated hosted virtual machine instance. For example, the DNS server 112 can reference a table that identifies the instance identifier with the unique identifier included in the network computing provider URL and transmit a request to the network computing provider 106 as part of an API. In another embodiment, the network computing provider 106 can maintain information related to the instantiation state of a number of hosted virtual machine instances that can be polled. In this embodiment, the network computing provider 106 would periodically poll for the status of a set of hosted virtual machine instances or be informed when a previously instantiated virtual machine instance has been terminated.











TABLE 3






Instance
Network
Routing



Unique Identifier
Identifier
Address
Information
Status







unique_identifier 1
1-xxx
123.45.678.90
None
Active


unique_identifier 2
5-xxx
345.78.910.11
service level
Non-active


. . .
. . .
. . .
. . .
. . .


unique_identifier
67-xxx 
444.33.890.12
cost
Active


x1


information









With reference to the previous example, Table 3 illustrates an embodiment in which the DNS server components maintain information related to whether one or more previously instantiated virtual machine instances remain active. Additionally, the DNS servers can maintain information related to whether the active virtual machine instances available to process a subsequent requests.
With reference to FIG. 5A, if the previously instantiated hosted virtual machine instance is still instantiated and available to process subsequent requests, the DNS server can utilize network identifiers associated with the previously instantiated hosted virtual machine instance to resolve the DNS query. In one embodiment, at (1) the DNS server will resolve the DNS query by identifying the network address or an alternative identifier associated with the previously instantiated hosted virtual machine instance. At (2), the client computing device 102 utilizes the returned network address for the subsequent requests.
In an alternative embodiment, the DNS server may utilize additional request routing information to determine that a different virtual machine instance may be better suited to process the subsequent request by the client computing device 102. In one example, the processing of the request routing information may be indicative of lower cost estimates that may meet cost criteria for a different instantiated virtual machine instance of the network computing provider 106. In such embodiments, the DNS server 112 would transmit a request to instantiate a new hosted virtual machine instance in accordance with the request routing information.
In another example, the service provider 104 can utilize geographic criteria as additional request routing information. The geographic criteria can correspond to geographic-based regional service plans contracted between the service-provider 106 and the client computing device 102. Accordingly, a client computing device 102 DNS query received in a region not corresponding to the network computing provider 106's regional plan may be better processed by computing devices in a region corresponding to the network computing provider 106's regional plan.
In a further example, the service provider 104 can also analyze the DNS query according to service level criteria. The service level criteria can correspond to service or performance metrics contracted with the network computing provider 106. Examples of performance metrics can include latencies of data transmission between the service provider POPs and the client computing devices 102, total data provided on behalf of the network computing provider 106 by the service provider POPs, error rates for data transmissions, and the like.
In still a further example, the service provider 104 can process the DNS query according to network performance criteria. The network performance criteria can correspond to measurements of network performance for transmitting data from the service provider POPs to the client computing device 102. Examples of network performance metrics can include network data transfer latencies (measured by the client computing device or the network computing provider 106, network data error rates, and the like.
In yet a further example, the receiving DNS server process the DNS query for load balancing or load sharing purposes. The receiving DNS may obtain an identification of other POPs that define an order for such load balancing/load sharing. The list can be dynamic or periodically updated based on current network conditions.
With reference now to FIG. 5B, if the previously instantiated hosted virtual machine instance is not still instantiated and otherwise unavailable to process subsequent requests, the DNS server can cause the instantiation a new instance of the previously instantiated virtual machine instance. In one embodiment, at (1) the DNS server will transmit a request to instantiate a new version (e.g., “re-instantiate”) of the hosted virtual machine instance. At (2), the NCC processes the requests and begins to instantiate a hosted virtual machine instance corresponding to the request. At (3), the DNS server transmits network identifiers for the re-instantiated hosted virtual machine instance. At (4), the DNS server resolves the DNS query by identifying the network address or an alternative identifier associated with the previously instantiated hosted virtual machine instance. At (5), the client computing device 102 utilizes the returned network address for the subsequent requests.
With reference now to FIG. 6, a request routine 600 implemented by the service provider 104 to process DNS queries will be described. One skilled in the relevant art will appreciate that actions/steps outlined for routine 600 may be implemented by one or many computing devices/components that are associated with the service provider 104. Accordingly, routine 600 has been logically associated as being performed by the service provider 104.
At block 602, one of the DNS server components 112, 116, 122 receives a DNS query corresponding to a network computing provider URL. As previously discussed, the network computing provider URL includes an identifier corresponding a previously instantiated hosted virtual machine instance. The DNS portion of the network computing provider URL can be parsed to obtain the identifier. As previously discussed, in one embodiment, parsing of the DNS portion of the network computing provider URL can include parsing the “unique_identifier” information included in the DNS portion of the network computing provider URL. Alternatively, the DNS server may utilize all the DNS portion of the network computing provider URL as the “unique_identifier” portion, especially in embodiments in which no additional information utilized for request routing is included in the DNS portion of the network computing provider URL.
At block 604, the DNS server transmits a query to the network computing provider 106 to determine an instantiation state for a virtual machine instance associated with the unique identifier. Illustratively, the DNS server attempts to determine whether the previously instantiated hosted virtual machine is still instantiated and available to process a subsequent request from the client computing device 102. In one embodiment, the DNS server can transmit a request to the network service provider 106 to determine in real time or substantially real time whether the network computing provider 106 has terminated the previously instantiated hosted virtual machine instance or whether the hosted virtual machine instance is otherwise unavailable. For example, the DNS server can transmit a request including a hosted virtual machine identifier in accordance with an API.
In another embodiment, the DNS server components or a different component of the service provider 104 can maintain information related to the instantiation state of a number of hosted virtual machine instances that can be polled. In this embodiment, the service provider 104 would periodically poll for the status of a set of hosted virtual machine instances or be informed when a previously instantiated virtual machine instance has been terminated. Accordingly, the transmission of the query regarding the instantiation state may include internal queries to the information maintained by the DNS components (or other components), a transmittal to external components, or combination thereof.
At decision block 606, a test is conducted to determine whether the selected hosted virtual machine instance is active and available to process requests if the previously instantiated hosted virtual machine instance is still instantiated and available to process subsequent requests. Illustratively, decision block 606 can correspond to an initial determination of whether one or more virtual machine instances have been previously instantiated. If so, decision block 606 would further determine whether the selected hosted virtual machine instance is still instantiated and otherwise available to process subsequent requests. If the selected hosted virtual machine instance is active and available to process requests, at block 608, the service provider 104 identifies network identifiers associated with the previously instantiated hosted virtual machine instance to resolve the DNS query. By way of illustrative example, the DNS component of the service provider 104 can utilize the table that maintains the network address of the hosted virtual machine instance to use in the resolution of the DNS query.
At decision block 610, a test is conducted to determine whether the service provider 104 should utilize a new instantiation of a hosted virtual machine instance even if the previously hosted virtual machine instance may still be instantiated. As previously described, the DNS server may utilize additional request routing information to determine that a different virtual machine instance may be better suited to process the subsequent request by the client computing device 102. In another embodiment, the network computing provider 106 may indicate that while a virtual machine instance may still be active, the network computing provider 106 would like to migrate the virtual machine instance or otherwise initiate one or more additional virtual machine instances in the place of the current virtual machine instance. If a new instantiation is determined, the routine 600 proceeds to block 614, which will be described below. Alternatively, if no new instantiation is required, at block 618, the DNS server will resolve the DNS query by identifying the network address or an alternative identifier associated with the previously instantiated hosted virtual machine instance.
Returning to decision block 606, if the previously instantiated hosted virtual machine instance has not been previously instantiate or if a previously instantiated hosted virtual machine instance is not still instantiated based on management decisions by the network computing provider 106, or if a previously instantiated hosted virtual machine instances is otherwise unavailable to process subsequent requests, the DNS server can cause the instantiation a new instance of the previously instantiated virtual machine instance. At block 614, in one embodiment, the DNS server will transmit a request to instantiate a new version (e.g., “re-instantiate”) of the hosted virtual machine instance. As previously discussed, the NCC processes the requests and begins to instantiate a hosted virtual machine instance corresponding to the request. In another embodiment, if the hosted virtual machine instance has not been previously instantiated (or was terminated by the customer), the DNS server will transmit a request to create a new instantiation of a hosted virtual machine instance. As previously discussed, the NCC processes the requests and begins to instantiate a hosted virtual machine instance corresponding to the request based on the configuration information maintained for by the DNS server. At block 616, the DNS server receives the network identifiers for the re-instantiated hosted virtual machine instance. At block 618, the DNS server resolves the DNS query by identifying the network address or an alternative identifier associated with the previously instantiated hosted virtual machine instance and the routine 600 terminates.
While illustrative embodiments have been disclosed and discussed, one skilled in the relevant art will appreciate that additional or alternative embodiments may be implemented within the spirit and scope of the present invention. Additionally, although many embodiments have been indicated as illustrative, one skilled in the relevant art will appreciate that the illustrative embodiments do not need to be combined or implemented together. As such, some illustrative embodiments do not need to be utilized or implemented in accordance with scope of variations to the present disclosure.
Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment.
Any process descriptions, elements, or blocks in the flow diagrams described herein and/or depicted in the attached FIGS. should be understood as potentially representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps in the process. Alternate implementations are included within the scope of the embodiments described herein in which elements or functions may be deleted, executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those skilled in the art. It will further be appreciated that the data and/or components described above may be stored on a computer-readable medium and loaded into memory of the computing device using a drive mechanism associated with a computer readable storing the computer executable components such as a CD-ROM, DVD-ROM, or network interface further, the component and/or data can be included in a single device or distributed in any manner. Accordingly, general purpose computing devices may be configured to implement the processes, algorithms and methodology of the present disclosure with the processing and/or execution of the various data and/or components described above.
It should be emphasized that many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.

## Claims

1. A method for request routing comprising:
obtaining, by a DNS processing service, a DNS query from a client computing device, wherein the DNS query corresponds to a resource identifier associated with a previously instantiated hosted virtual machine instance, wherein the DNS query includes an identifier associated with the previously instantiated hosted virtual machine instance, and wherein the resource identifier and the identifier associated with the previously instantiated hosted virtual machine instance are different;
parsing, by the DNS processing service, a DNS portion of the DNS query to obtain the identifier associated with the previously instantiated hosted virtual machine instance;
determining, by the DNS processing service, whether the previously instantiated hosted virtual machine is instantiated and available to process subsequent requests from the client computing device;
if the previously instantiated hosted virtual machine is instantiated and available to process subsequent requests from the client computing device, resolving, by the DNS processing service, the DNS query by transmitting information associated with the previously instantiated hosted virtual machine instance; and
if the previously instantiated hosted virtual machine instance is not instantiated and available to process subsequent requests from the client computing device,
transmitting, by the DNS processing service, a request to re-instantiate the previously instantiated hosted virtual machine;
obtaining, by the DNS processing service, information corresponding to the re-instantiation of the previously instantiated hosted virtual machine; and
resolving, by the DNS processing service, the DNS query by transmitting information associated with the re-instantiated hosted virtual machine instance.

2. The method as recited in claim 1, wherein parsing the DNS portion of the DNS query to obtain the identifier associated with the previously instantiated hosted virtual machine instance includes parsing a complete DNS portion of the DNS query.

3. The method as recited in claim 1, wherein parsing the DNS portion of the DNS query to obtain the identifier associated with the previously instantiated hosted virtual machine instance includes parsing a sub-portion of the DNS portion of the DNS query.

4. The method as recited in claim 1, wherein resolving the DNS query by transmitting information associated with the re-instantiated hosted virtual machine instance includes transmitting a canonical name record identifier associated with a service provider hosting the previously instantiated hosted virtual machine instance.

5. The method as recited in claim 1, wherein resolving the DNS query by transmitting information associated with the re-instantiated hosted virtual machine instance includes transmitting a network address associated with a service provider hosting the previously instantiated hosted virtual machine instance.

6. The method as recited in claim 1 further comprising maintaining, for a set of previously instantiated virtual machine instances, information related to an availability to process subsequent requests from the client computing device.

7. The method as recited in claim 6 further comprising:
periodically transmitting requests related to availability to process subsequent requests from the client computing device for the set of previously instantiated virtual machine instances;
obtaining updated information related to availability to process subsequent requests from the client computing device for the set of previously instantiated virtual machine instances;
updating the information related to an availability to process subsequent requests from the client computing device responsive to the updated information;
obtaining a request from the client computing device for the requested content; and
processing and transmitting the requested content from the selected network computing component in response to the request from the client computing device.

8. A method for request routing comprising:
obtaining, by a DNS processing service, a DNS query from a client computing device, wherein the DNS query corresponds to a resource identifier associated with a previously instantiated hosted virtual machine instance, wherein the DNS query includes an identifier associated with the previously instantiated hosted virtual machine instance, and wherein the resource identifier and the identifier associated with the previously instantiated hosted virtual machine instance are different;
determining, by the DNS processing service, whether the previously instantiated hosted virtual machine associated with the DNS query is instantiated and available to process subsequent requests from the client computing device; and
if the previously instantiated hosted virtual machine instance is not instantiated and available to process subsequent requests from the client computing device, resolving, by the DNS processing service, the DNS query by transmitting information associated with a re-instantiation of the previously instantiated hosted virtual machine instance.

9. The method as recited in claim 8, wherein if the previously instantiated hosted virtual machine is instantiated and available to process subsequent requests from the client computing device, resolving the DNS query by transmitting information associated with the previously instantiated hosted virtual machine instance.

10. The method as recited in claim 9, wherein prior to resolving the DNS query by transmitting information associated with the previously instantiated hosted virtual machine instance, determining whether a new instantiation of the previously instantiated hosted virtual machine instance should be initiated.

11. The method as recited in claim 10, wherein determining whether a new instantiation of the previously instantiated hosted virtual machine instance should be initiated includes evaluating updated request routing information corresponding to the DNS query.

12. The method as recited in claim 8 further comprising parsing a DNS portion of the DNS query to obtain the identifier associated with the previously instantiated hosted virtual machine instance.

13. The method as recited in claim 8 further comprising maintaining, for a set of previously instantiated virtual machine instances, information related to an availability to process subsequent requests from the client computing device.

14. The method as recited in claim 13 further comprising:
periodically transmitting requests related to availability to process subsequent requests from the client computing device for the set of previously instantiated virtual machine instances;
obtaining updated information related to availability to process subsequent requests from the client computing device for the set of previously instantiated virtual machine instances; and
updating the information related to an availability to process subsequent requests from the client computing device responsive to the updated information.

15. The method as recited in claim 8, wherein resolving the DNS query by transmitting information associated with a re-instantiation of the previously instantiated hosted virtual machine instance includes:
transmitting, by the DNS processing service, a request to re-instantiate the previously instantiated hosted virtual machine;
obtaining, by the DNS processing service, information corresponding to the re instantiation of the previously instantiated hosted virtual machine; and
resolving, by the DNS processing service, the DNS query by transmitting information associated with the re-instantiated hosted virtual machine instance.

16. A method for request routing comprising:
obtaining, by a DNS processing service, a DNS query from a client computing device, wherein the DNS query corresponds to a resource identifier associated with a previously instantiated hosted virtual machine instance, wherein the DNS query includes an identifier associated with the previously instantiated hosted virtual machine instance, and wherein the resource identifier and the identifier associated with the previously instantiated hosted virtual machine instance are different;
evaluating, by the DNS processing service, whether the previously instantiated hosted virtual machine associated with the DNS query is instantiated; and
if the previously instantiated hosted virtual machine instance is not instantiated, resolving, by the DNS processing service, the DNS query by transmitting information associated with a re-instantiation of the previously instantiated hosted virtual machine instance.

17. The method as recited in claim 16, wherein if the previously instantiated hosted virtual machine is instantiated, resolving the DNS query by transmitting information associated with the previously instantiated hosted virtual machine instance.

18. The method as recited in claim 17, wherein prior to resolving the DNS query by transmitting information associated with the previously instantiated hosted virtual machine instance, determining whether a new instantiation of the previously instantiated hosted virtual machine instance should be initiated.

19. The method as recited in claim 18, wherein determining whether a new instantiation of the previously instantiated hosted virtual machine instance should be initiated includes evaluating updated request routing information corresponding to the DNS query.

20. The method as recited in claim 16 further comprising parsing a DNS portion of the DNS query to obtain the identifier associated with the previously instantiated hosted virtual machine instance.

21. The method as recited in claim 20, wherein parsing the DNS portion of the DNS query includes obtaining an identifier identifying the previously instantiated hosted virtual machine instance from the DNS portion of the DNS query.

22. The method as recited in claim 20, wherein parsing the DNS portion of the DNS query includes obtaining additional request routing information from the DNS portion of the DNS query.

23. The method as recited in claim 16 further comprising maintaining, for a set of previously instantiated virtual machine instances, information related a current instantiation state for the set of previously instantiated virtual machine instances.

24. The method as recited in claim 23 further comprising:
periodically transmitting requests related an instantiation state for the set of previously instantiate virtual machine instances;
obtaining updated information related instantiation state for the set of previously instantiate virtual machine instances; and
updating the information related to the instantiation state for the set of previously instantiate virtual machine instances.

25. The method as recited in claim 16, wherein resolving the DNS query by transmitting information associated with a re-instantiation of the previously instantiated hosted virtual machine instance includes:
transmitting, by the DNS processing service, a request to re-instantiate the previously instantiated hosted virtual machine;
obtaining, by the DNS processing service, information corresponding to the re instantiation of the previously instantiated hosted virtual machine; and
resolving, by the DNS processing service, the DNS query by transmitting information associated with the re-instantiated hosted virtual machine instance.