Abstract: Example methods and network devices for tunnel-based routing calculation. One example method may comprise establishing a tunnel between a first tunnel interface and a second tunnel interface; establishing a first session for routing information exchange between a first tunnel endpoint and an underlay network device; establishing a second session for routing information exchange between the first tunnel interface and the second tunnel interface over the tunnel. In response to receiving first routing information over the first session, the underlay network device may be configured to be a next hop to reach the second tunnel endpoint by updating a routing table to include a first entry. Further, the underlay network device may be retained as the next hop by updating the routing table to include a second entry to override second routing information that advertises, over the second session, the second tunnel interface as the next hop.

Abstract: Some embodiments provide a method for a host computer that executes a set of data compute nodes (DCNs), for identifying a designated router for a multicast group. The method receives a membership request message to join the multicast group from a particular DCN of the set of DCNs, the membership request message including an address associated with the multicast group. The method identifies a logical router gateway from a set of logical router gateways as the designated router for the multicast group, based at least in part on the address associated with the multicast group, where different logical router gateways from the set of logical router gateways are assigned as designated routers for different multicast groups with different associated addresses. The method forwards the membership request message to the identified logical router gateway.

Abstract: Some embodiments provide a method for a controller that manages a physical network that implements multiple logical networks that include multiple logical routers. The method receives a command to change a particular centralized routing component of a logical router to an inactive state. At least two centralized routing components of the logical router are implemented on at least two different host machines in the physical network. The method identifies a host machine on which the particular centralized routing component operates. Other centralized routing components of other logical routers also operate on the identified host machine. The method sends a message to the identified host machine to cause the particular centralized routing component to change to an inactive state, without modifying a state of the identified host machine or the other centralized routing components operating on the identified host machine.

Abstract: Example methods and network devices for tunnel-based routing calculation. One example method may comprise establishing a tunnel between a first tunnel interface and a second tunnel interface; establishing a first session for routing information exchange between a first tunnel endpoint and an underlay network device; establishing a second session for routing information exchange between the first tunnel interface and the second tunnel interface over the tunnel. In response to receiving first routing information over the first session, the underlay network device may be configured to be a next hop to reach the second tunnel endpoint by updating a routing table to include a first entry. In response to receiving second routing information from the second tunnel interface over the second session, the underlay network device may be retained as the next hop based on an excluded address specified in the second routing information.

Abstract: In some embodiments, a method for selecting an egress point for accessing an external network associated with a distributed logical router that is distributed across at least a first computing device and a second computing device is provided. The method receives, by an instance of the logical router at the first computing device, first identification information and a first preference value. The method compares the first preference value to a second preference value. The second preference value is associated with second identification information corresponding to a current computing device that is identified as a current preferred egress point for the logical router. The method determines whether to set the egress point connected to the instance of the logical router in the second computing device as a new preferred egress point for the logical router.

Abstract: A method for identifying a first hop router (“FHR”) in a distributed virtualized network is presented. In an embodiment, a method comprises receiving a multicast message on an incoming interface. In response to receiving the multicast message, the router determines whether the router is a FHR for the multicast message, i.e., whether, in response to generating and transmitting a hello multicast message, the router does not receive a response on the incoming interface; or whether an interface to a RP for the multicast message is different than the incoming interface. If the router is the FHR for the multicast message, then the router determines an IP address of a RP for the multicast message. The router also encapsulates the multicast message into a unicast message, includes in the unicast message the IP address of the RP as a destination address, and transmits the unicast message to the RP.

Abstract: Example methods and network devices for tunnel-based routing calculation. One example method may comprise establishing a tunnel between a first tunnel interface and a second tunnel interface; establishing a first session for routing information exchange between a first tunnel endpoint and an underlay network device; establishing a second session for routing information exchange between the first tunnel interface and the second tunnel interface over the tunnel. In response to receiving first routing information over the first session, the underlay network device may be configured to be a next hop to reach the second tunnel endpoint by updating a routing table to include a first entry. In response to receiving second routing information from the second tunnel interface over the second session, the underlay network device may be retained as the next hop based on an excluded address specified in the second routing information.

Abstract: Example methods and network devices for tunnel-based routing calculation. One example method may comprise establishing a tunnel between a first tunnel interface and a second tunnel interface; establishing a first session for routing information exchange between a first tunnel endpoint and an underlay network device; establishing a second session for routing information exchange between the first tunnel interface and the second tunnel interface over the tunnel. In response to receiving first routing information over the first session, the underlay network device may be configured to be a next hop to reach the second tunnel endpoint by updating a routing table to include a first entry. Further, the underlay network device may be retained as the next hop by updating the routing table to include a second entry to override second routing information that advertises, over the second session, the second tunnel interface as the next hop.

Abstract: In some embodiments, a method receives a selection of a logical router in the first computing device in a first site of a plurality of sites as a preferred egress point to an external network for the logical router. The logical router is instantiated on computing devices in the plurality of sites and a single site in the sites is the preferred egress point for the logical router. The method stores identification information for the logical router in a routing table that stores identification information for multiple logical routers. The identification information is unique among multiple logical routers. The method advertises via a routing instance in a control plane to other computing devices in other sites the identification information for the logical router to indicate the logical router in the first computing device in the first site is the preferred egress point.

Abstract: Embodiments described herein involve appliance migration. Embodiments include connecting, by a second appliance that is configured to perform a service, to a first uplink and a first downlink of a first appliance that is configured to perform the service. Embodiments include connecting, by the second appliance, to a first endpoint and a second endpoint to which the first appliance is connected. Embodiments include determining, by the second appliance, existing flows processed by the first appliance. Embodiments include processing, by the second appliance, a plurality of packets received via the first endpoint by: forwarding, by the second appliance, first packets of the plurality of packets that correspond to the existing flows to the first appliance; and performing, by the second appliance, the service for second packets of the plurality of packets that do not correspond to the existing flows.

Abstract: Embodiments described herein involve appliance migration. Embodiments include connecting, by a second appliance that is configured to perform a service, to a first uplink and a first downlink of a first appliance that is configured to perform the service. Embodiments include connecting, by the second appliance, to a first endpoint and a second endpoint to which the first appliance is connected. Embodiments include determining, by the second appliance, existing flows processed by the first appliance. Embodiments include processing, by the second appliance, a plurality of packets received via the first endpoint by: forwarding, by the second appliance, first packets of the plurality of packets that correspond to the existing flows to the first appliance; and performing, by the second appliance, the service for second packets of the plurality of packets that do not correspond to the existing flows.

Abstract: Some embodiments provide a method for implementing a logical network. Based on logical network configuration data, the method identifies a route for a set of network addresses to add to a routing table of the logical router, and also identifies a route type for the identified route. The method determines whether to include the identified route as a route for the logical router to advertise based on the route type of the identified route. The method distributes a routing table comprising the identified route to a computing device that implements the logical router, where the computing device advertises the identified route when the route type is specified for advertisement.

Abstract: Some embodiments provide method for implementing a logical router of a logical network. The method receives a configuration for a first logical router. The configuration includes a static route for the first logical router. The method defines several routing components with separate routing tables for the logical router. The method adds a first route, having a first static route type, for the static route to the routing tables of at least a first subset of the routing components. Based on the connection of a second logical router to the first logical router, adding a second route, having a second static route type, to the routing tables of at least a second subset of the routing components.

Abstract: The technology disclosed herein enables synchronization of routing information between at least two edge systems in an edge system cluster. In a particular embodiment, a method provides, in each of the edge systems, receiving network routing information from a plurality of routers that route outbound network traffic from the edge systems and synchronizing the network routing information between the edge systems. Additionally, in each of the edge systems, the method provides receiving outbound network traffic via a logical router spanning the edge systems and routing the outbound network traffic from the edge systems in accordance with the network routing information after synchronization.

Abstract: In some embodiments, a method receives a selection of a logical router in the first computing device in a first site of a plurality of sites as a preferred egress point to an external network for the logical router. The logical router is instantiated on computing devices in the plurality of sites and a single site in the sites is the preferred egress point for the logical router. The method stores identification information for the logical router in a routing table that stores identification information for multiple logical routers. The identification information is unique among multiple logical routers. The method advertises via a routing instance in a control plane to other computing devices in other sites the identification information for the logical router to indicate the logical router in the first computing device in the first site is the preferred egress point.

Abstract: For a multi-tenant environment, some embodiments of the invention provide a novel method for (1) embedding a specific path for a tenant's data message flow through a network in tunnel headers encapsulating the data message flow, and then (2) using the embedded path information to direct the data message flow through the network. In some embodiments, the method selects the specific path from two or more viable such paths through the network for the data message flow.

Abstract: Some embodiments provide a method for a network controller operating on a host machine that hosts a particular one of multiple centralized routing components for a logical router. The method receives a routing table from a routing protocol application operating on the host machine. Each of the other centralized routing components operates on a different host machine and implements a different interface of the logical router that connects to at least one physical router external to the logical network. The routing protocol application operates as a router server for all of the centralized routing components. For each of the other centralized routing components, the method identifies a set of routes in the routing table to distribute to the centralized routing component. The method sends the identified routes for each centralized routing component to the centralized routing component.

Abstract: For a multi-tenant environment, some embodiments of the invention provide a novel method for (1) embedding a specific path for a tenant's data message flow through a network in tunnel headers encapsulating the data message flow, and then (2) using the embedded path information to direct the data message flow through the network. In some embodiments, the method selects the specific path from two or more viable such paths through the network for the data message flow.

Abstract: Some embodiments provide method for implementing a logical router of a logical network. The method receives a configuration for a first logical router. The configuration includes a static route for the first logical router. The method defines several routing components with separate routing tables for the logical router. The method adds a first route, having a first static route type, for the static route to the routing tables of at least a first subset of the routing components. Based on the connection of a second logical router to the first logical router, adding a second route, having a second static route type, to the routing tables of at least a second subset of the routing components.

Abstract: Some embodiments provide a method for a computing device that implements a centralized logical routing component of a logical network that handles data traffic between the logical network and an external physical network. The method receives a first routing protocol message from a machine that implements a route server for a distributed logical routing component of the logical network. The first routing protocol message includes (i) a parameter identifying the machine as a route server and (ii) a set of logical network addresses. The method receives a second routing protocol message from the route server that specifies a next hop address for the set of logical network addresses. The method adds a route specifying the next hop address for the set of logical network addresses to a routing table of the centralized logical routing component. The added route has a higher priority than routes received from the external physical network.