Abstract: Some embodiments provide a novel method of performing health monitoring for resources associated with a global server load balancing (GSLB) system. This system is implemented by several domain name system (DNS) servers that perform DNS services for resources located at several geographically separate sites. The method identifies several different groupings of the resources. It then assigns the health monitoring of the different resource groups to different DNS servers. The method then configures each particular DNS server (1) to send health monitoring messages to the particular group of resources assigned to the particular DNS server, (2) to generate data by analyzing responses to the sent health monitoring messages, and (3) to distribute the generated data to the other DNS servers. The method in some embodiments is performed by a set of one or more controllers.

Abstract: Some embodiments provide a two-tier DNS (Domain Name System) service for processing DNS requests. In some embodiments, the two-tier DNS service deploys first and second tiers of service machines, with the second-tier having several groups of service machines each of which is configured to resolve DNS requests for a different set of domain names than the other second-tier group(s). Each service machine in the first-tier is configured to identify the second-tier group responsible for each particular DNS request that the service machine receives for each particular domain name, and to forward the particular DNS request to the second-tier group that it identifies for the particular DNS request. The first-tier DNS service in some embodiments has only one group of service machines. Each first or second service machine group in some embodiments can have one or more service machines, and can be scaled up or down to add or remove service machines to the group (e.g., through an active/active layer 3 scaleout with BGP).

Abstract: Some embodiments provide a two-tier DNS (Domain Name System) service for processing DNS requests. In some embodiments, the two-tier DNS service deploys first and second tiers of service machines, with the second-tier having several groups of service machines each of which is configured to resolve DNS requests for a different set of domain names than the other second-tier group(s). Each service machine in the first-tier is configured to identify the second-tier group responsible for each particular DNS request that the service machine receives for each particular domain name, and to forward the particular DNS request to the second-tier group that it identifies for the particular DNS request. The first-tier DNS service in some embodiments has only one group of service machines. Each first or second service machine group in some embodiments can have one or more service machines, and can be scaled up or down to add or remove service machines to the group (e.g., through an active/active layer 3 scaleout with BGP).

Abstract: Some embodiments provide a two-tier DNS (Domain Name System) service for processing DNS requests. In some embodiments, the two-tier DNS service deploys first and second tiers of service machines, with the second-tier having several groups of service machines each of which is configured to resolve DNS requests for a different set of domain names than the other second-tier group(s). Each service machine in the first-tier is configured to identify the second-tier group responsible for each particular DNS request that the service machine receives for each particular domain name, and to forward the particular DNS request to the second-tier group that it identifies for the particular DNS request. The first-tier DNS service in some embodiments has only one group of service machines. Each first or second service machine group in some embodiments can have one or more service machines, and can be scaled up or down to add or remove service machines to the group (e.g., through an active/active layer 3 scaleout with BGP).

Abstract: Providing a distributed network service includes: receiving network traffic at a first physical device; and executing a service engine to participate in the distributed network service. The distributed network service is provided to at least the first target application instance executing in a first VM on the first physical device, and a second target application instance executing in a second VM on a second physical device; and a shared state of the distributed network service is maintained with respect to the first physical device and the second physical device.

Abstract: Providing a distributed network service includes: receiving network traffic at a first physical device; and executing a service engine to participate in the distributed network service. The distributed network service is provided to at least the first target application instance executing in a first VM on the first physical device, and a second target application instance executing in a second VM on a second physical device; and a shared state of the distributed network service is maintained with respect to the first physical device and the second physical device.

Abstract: Migrating a network service that is currently being performed by a first device to be performed by a second device includes: instructing the second device to notify an upstream network device to forward traffic that is to be serviced by the network service to the second device instead of to the first device, the network service being associated with an Internet Protocol (IP) address; and instructing the first device to migrate the network service to the second device, wherein the migration includes moving or copying state information associated with an existing flow currently serviced by the first device to the second device; the existing flow being an existing flow between a client application and a network application.

Abstract: Some embodiments provide a novel method of performing health monitoring for resources associated with a global server load balancing (GSLB) system. This system is implemented by several domain name system (DNS) servers that perform DNS services for resources located at several geographically separate sites. The method identifies several different groupings of the resources. It then assigns the health monitoring of the different resource groups to different DNS servers. The method then configures each particular DNS server (1) to send health monitoring messages to the particular group of resources assigned to the particular DNS server, (2) to generate data by analyzing responses to the sent health monitoring messages, and (3) to distribute the generated data to the other DNS servers. The method in some embodiments is performed by a set of one or more controllers.

Abstract: An example method of performing an upgrade operation for a distributed service in a virtualized computing system is described. The virtualized computing system includes a host cluster, the host cluster having hosts and a virtualization layer executing on hardware platforms of the hosts. The method includes: receiving, at a controller of the distributed service, a first upgrade operation from a user, the distributed service including the controller and a plurality of service engine groups, each of the plurality of service engine groups including a plurality of service engines; and performing, by the controller, the first upgrade operation on software of the controller exclusive of software of the service engines in each of the service engine groups, the software of the controller and the software of the plurality of service engines in each of the plurality of service engine groups executing in a plurality of hosts.

Abstract: Some embodiments provide a novel method of performing health monitoring for resources associated with a global server load balancing (GSLB) system. This system is implemented by several domain name system (DNS) servers that perform DNS services for resources located at several geographically separate sites. The method identifies several different groupings of the resources. It then assigns the health monitoring of the different resource groups to different DNS servers. The method then configures each particular DNS server (1) to send health monitoring messages to the particular group of resources assigned to the particular DNS server, (2) to generate data by analyzing responses to the sent health monitoring messages, and (3) to distribute the generated data to the other DNS servers. The method in some embodiments is performed by a set of one or more controllers.

Abstract: An example method of performing an upgrade operation for a distributed service in a virtualized computing system is described. The virtualized computing system includes a host cluster, the host cluster having hosts and a virtualization layer executing on hardware platforms of the hosts. The method includes: receiving, at a controller of the distributed service, a first upgrade operation from a user, the distributed service including the controller and a plurality of service engine groups, each of the plurality of service engine groups including a plurality of service engines; and performing, by the controller, the first upgrade operation on software of the controller exclusive of software of the service engines in each of the service engine groups, the software of the controller and the software of the plurality of service engines in each of the plurality of service engine groups executing in a plurality of hosts.

Abstract: Some embodiments provide a novel method of performing health monitoring for resources associated with a global server load balancing (GSLB) system. This system is implemented by several domain name system (DNS) servers that perform DNS services for resources located at several geographically separate sites. The method identifies several different groupings of the resources. It then assigns the health monitoring of the different resource groups to different DNS servers. The method then configures each particular DNS server (1) to send health monitoring messages to the particular group of resources assigned to the particular DNS server, (2) to generate data by analyzing responses to the sent health monitoring messages, and (3) to distribute the generated data to the other DNS servers. The method in some embodiments is performed by a set of one or more controllers.

Abstract: Providing a distributed network service includes: receiving network traffic at a first physical device; and executing a service engine to participate in the distributed network service. The distributed network service is provided to at least the first target application instance executing in a first VM on the first physical device, and a second target application instance executing in a second VM on a second physical device; and a shared state of the distributed network service is maintained with respect to the first physical device and the second physical device.

Abstract: Providing a distributed network service includes: receiving network traffic at a first physical device; and executing a service engine to participate in the distributed network service. The distributed network service is provided to at least the first target application instance executing in a first VM on the first physical device, and a second target application instance executing in a second VM on a second physical device; and a shared state of the distributed network service is maintained with respect to the first physical device and the second physical device.

Abstract: Migrating a network service that is currently being performed by a first device to be performed by a second device includes: instructing the second device to notify an upstream network device to forward traffic that is to be serviced by the network service to the second device instead of to the first device, the network service being associated with an Internet Protocol (IP) address; and instructing the first device to migrate the network service to the second device, wherein the migration includes moving or copying state information associated with an existing flow currently serviced by the first device to the second device; the existing flow being an existing flow between a client application and a network application.

Abstract: Migrating a network service that is currently being performed by a first device to be performed by a second device includes: instructing the second device to notify an upstream network device to forward traffic that is to be serviced by the network service to the second device instead of to the first device, the network service being associated with an Internet Protocol (IP) address; and instructing the first device to migrate the network service to the second device, wherein the migration includes moving or copying state information associated with an existing flow currently serviced by the first device to the second device; the existing flow being an existing flow between a client application and a network application.

Abstract: Some embodiments provide a novel method of performing health monitoring for resources associated with a global server load balancing (GSLB) system. This system is implemented by several domain name system (DNS) servers that perform DNS services for resources located at several geographically separate sites. The method identifies several different groupings of the resources. It then assigns the health monitoring of the different resource groups to different DNS servers. The method then configures each particular DNS server (1) to send health monitoring messages to the particular group of resources assigned to the particular DNS server, (2) to generate data by analyzing responses to the sent health monitoring messages, and (3) to distribute the generated data to the other DNS servers. The method in some embodiments is performed by a set of one or more controllers.

Abstract: Some embodiments provide a novel method of performing health monitoring for resources associated with a global server load balancing (GSLB) system. This system is implemented by several domain name system (DNS) servers that perform DNS services for resources located at several geographically separate sites. The method identifies several different groupings of the resources. It then assigns the health monitoring of the different resource groups to different DNS servers. The method then configures each particular DNS server (1) to send health monitoring messages to the particular group of resources assigned to the particular DNS server, (2) to generate data by analyzing responses to the sent health monitoring messages, and (3) to distribute the generated data to the other DNS servers. The method in some embodiments is performed by a set of one or more controllers.

Abstract: Providing a distributed network service includes: receiving network traffic at a first physical device; and executing a service engine to participate in the distributed network service. The distributed network service is provided to at least the first target application instance executing in a first VM on the first physical device, and a second target application instance executing in a second VM on a second physical device; and a shared state of the distributed network service is maintained with respect to the first physical device and the second physical device.

Abstract: Providing a distributed network service includes: receiving network traffic at a first physical device; and executing a service engine to participate in the distributed network service. The distributed network service is provided to at least the first target application instance executing in a first VM on the first physical device, and a second target application instance executing in a second VM on a second physical device; and a shared state of the distributed network service is maintained with respect to the first physical device and the second physical device.