Abstract: Some embodiments provide a method for determining a realization status of one or more logical entities of a logical network. The method, each time a particular event occurs, increments the value of a realization number and publishes the incremented value to a set of controllers of the logical network. Upon receiving data that specifies the state of a logical entity of the logical network, the method publishes the logical entity state's data to the set of controllers. In some embodiments, the method queries the set of controllers for a realization status of the state data for a set of logical entities that is published to the set of controllers up to a particular point of time. The submitted query, in some embodiments, includes a particular value of the realization number associated with the particular point of time.

Abstract: Certain embodiments described herein are generally directed to processing domain objects in a distributed system using logical sharding. In some embodiments, a central control plane (CCP) node receives a domain object. In some embodiments, if the CCP node determines that the domain object is not already present in a shared data store and that the CCP node is the logical master of the domain object, the CCP node generates a status based on the domain object, and stores the status and domain object in the shared data store. In some embodiments, the shared data store notifies the plurality of CCP nodes of the stored status and domain object.

Abstract: A network control system that achieves high availability for forwarding state computation within a controller cluster by replicating different levels of table state between controllers of the controller cluster. To build a highly available controller cluster, the tables for storing the forwarding state are replicated across the controllers. In order to reduce network traffic between the controllers, fewer tables are replicated to slave controllers, which then recompute the forwarding state of the master controller in order to have a replicate copy of the master controller's forwarding state for possible failover. In other embodiments, more tables are replicated to minimize the recomputations and processor load on the slave controller. The network control system of some embodiments performs continuous snapshotting to minimize downtime associated with reaching a fixed point and replicating the state.

Abstract: Some embodiments provide a method for a first network controller that manages a set of logical forwarding elements implemented in several managed forwarding elements. The method receives a request to trace a specified packet having a particular source on a logical forwarding element. The method generates the packet according to the packet specification. The generated packet includes an indicator that the packet is for a trace operation. The method sends the packet to a second network controller that manages a managed forwarding element associated with the particular source. The method receives a first set of messages regarding operations performed on the packet from a set of network controllers that receives a second set of messages regarding operations performed on the packet from a set of managed forwarding elements that process the packet.

Abstract: Some embodiments provide a method for determining a realization status of one or more logical entities of a logical network. The method, each time a particular event occurs, increments the value of a realization number and publishes the incremented value to a set of controllers of the logical network. Upon receiving data that specifies the state of a logical entity of the logical network, the method publishes the logical entity state's data to the set of controllers. In some embodiments, the method queries the set of controllers for a realization status of the state data for a set of logical entities that is published to the set of controllers up to a particular point of time. The submitted query, in some embodiments, includes a particular value of the realization number associated with the particular point of time.

Abstract: Some embodiments provide a method for identifying a realization status of one or more logical entities of a logical network. In some embodiments the method is implemented by a controller that controls network data communications in a logical network. The method receives a request for realization status of a set of logical entities at a particular point of time that is associated with a particular value of a realization number. The method determines whether configuration data up to the particular point of time for each logical entity in the set has been processed and distributed to a set of local controllers that operates on a set of host machines. The method returns a realization reply that includes a successful realization message when the configuration data up to the particular point in time for each logical entity in the set has been processed and distributed to the set of local controllers.

Abstract: A network control system that achieves high availability for forwarding state computation within a controller cluster by replicating different levels of table state between controllers of the controller cluster. To build a highly available controller cluster, the tables for storing the forwarding state are replicated across the controllers. In order to reduce network traffic between the controllers, fewer tables are replicated to slave controllers, which then recompute the forwarding state of the master controller in order to have a replicate copy of the master controller's forwarding state for possible failover. In other embodiments, more tables are replicated to minimize the recomputations and processor load on the slave controller. The network control system of some embodiments performs continuous snapshotting to minimize downtime associated with reaching a fixed point and replicating the state.

Abstract: Some embodiments provide a method for a first network controller that manages a set of logical forwarding elements implemented in several managed forwarding elements. The method receives a request to trace a specified packet having a particular source on a logical forwarding element. The method generates the packet according to the packet specification. The generated packet includes an indicator that the packet is for a trace operation. The method sends the packet to a second network controller that manages a managed forwarding element associated with the particular source. The method receives a first set of messages regarding operations performed on the packet from a set of network controllers that receives a second set of messages regarding operations performed on the packet from a set of managed forwarding elements that process the packet.

Abstract: Some embodiments provide a novel network control system that provides publications for managing different slices (e.g., logical and/or physical entities) of a network. The publications are published from publisher controllers in the network control system to subscriber controllers. The network control system uses publications with generation numbers and buffered subscribers to implement the fixed points in order to help maintain a consistent network state. Buffered subscribers buffer the inputs received from a publisher in case the publisher becomes unavailable. Rather than deleting all of the output state that is based on the published inputs, the buffered subscriber allows the subscriber to maintain the network state until an explicit change to the state is received at the subscriber from a publisher (e.g., a restarted publisher, a backup publisher, etc.).

Abstract: Some embodiments provide a method for a network controller that manages a flow-based managed forwarding element (MFE). The method receives multiple service rules for implementation by the MFE. Each service rule matches over a set of network addresses. At least one network address is in the set of network addresses for at least two service rules. The method groups the network addresses into non-overlapping groups of network addresses, each of which addresses that are all matched by only a same set of service rules. The method generates flow entries that match over the groups of network addresses for the MFE to use to implement the service rules.

Abstract: Some embodiments provide a method for a network controller. The method receives configuration data, for a logical router managed by the network controller, that specifies at least one logical port for the logical router. The method automatically generates connected routes for the logical router based on network address ranges specified for the logical ports of the logical router. The method receives a manually input static route for the logical router. The method generates data tuples, for distribution to several managed network elements, based on the connected and static routes for the logical router in order for the several managed network elements to implement the logical router.

Abstract: Some embodiments provide a method for an integrated network management and modification analysis system. At the integrated system, the method receives a proposed modification to configuration data for a logical network stored by the integrated system as a set of rules. Without implementing the proposed modification, the method analyzes changes to the rules that would occur based on the proposed modification. The method provides a graphical user interface (GUI) that indicates logical network entities affected by the proposed modification. In response to a command to implement the proposed modification, the method generates an updated set of rules at the integrated system and stores the updated set of rules for distribution to managed forwarding elements that implement the logical network.

Abstract: Some embodiments provide a novel network control system that uses secondary input queues to receive and store inputs from multiple input sources prior to moving the inputs to a primary input queue for processing. The secondary input queues provide a separate storage for each input source so that the inputs from the different sources do not get mixed with each other to ensure that fixed points and barriers sent to the controller maintain their integrity.

Abstract: Certain embodiments described herein are generally directed to processing domain objects in a distributed system using logical sharding. In some embodiments, a central control plane (CCP) node receives a domain object. In some embodiments, if the CCP node determines that the domain object is not already present in a shared data store and that the CCP node is the logical master of the domain object, the CCP node generates a status based on the domain object, and stores the status and domain object in the shared data store. In some embodiments, the shared data store notifies the plurality of CCP nodes of the stored status and domain object.

Abstract: Some embodiments provide a method for a network controller that manages several logical networks. The method receives a specification of a logical network that includes at least one logical forwarding element attached to a logical service (e.g., DHCP). The method selects at least one host machine to host the specified logical service from several host machines designated for hosting logical services. The method generates logical service configuration information for distribution to the selected host machine. In some embodiments, the method selects a master host machine and a backup host machine for hosting logical service. In some embodiments, a particular one of the designated host machines hosts at least two DHCP services for two different logical networks as separate processes operating on the particular host machine.

Abstract: Certain embodiments described herein are generally directed to determining the spans of logical entities in a logical network using a graph theoretic method. For example, in some embodiments, a configuration of the logical network is represented as a directed graph with labeled edges. The span of any logical entity in the logical network may then be computed based on the directed graph of the logical network. For example, for a given entity represented by a given node, the set of nodes that can be reached from the given node via span-depends-on edges only may be computed and referred to as the span base of the given node. Further, the set of all managed forwarding elements reachable from each node of the span base of the given node via contains edges only is the span for the given entity.

Abstract: Some embodiments provide a method for an application operating on a host machine. The method receives a configuration of a Dynamic Host Configuration Protocol (DHCP) service for implementation within a virtualized container on the host machine. The configuration includes several database table entries. The method converts the several database table entries into a configuration file for use by a process that operates in the virtualized container. the method initializes the process in the virtualized container. The process in the virtualized container reads the configuration file in order to perform DHCP services for machines connected to at least one logical forwarding element of a logical network.

Abstract: Some embodiments provide a method for a first network controller that manages a set of logical forwarding elements implemented in several managed forwarding elements. The method receives a request to trace a specified packet having a particular source on a logical forwarding element. The method generates the packet according to the packet specification. The generated packet includes an indicator that the packet is for a trace operation. The method sends the packet to a second network controller that manages a managed forwarding element associated with the particular source. The method receives a first set of messages regarding operations performed on the packet from a set of network controllers that receives a second set of messages regarding operations performed on the packet from a set of managed forwarding elements that process the packet.

Abstract: Some embodiments provide a method for a network controller that manages several logical networks. The method receives a specification of a logical network that includes at least one logical forwarding element attached to a logical service (e.g., DHCP). The method selects at least one host machine to host the specified logical service from several host machines designated for hosting logical services. The method generates logical service configuration information for distribution to the selected host machine. In some embodiments, the method selects a master host machine and a backup host machine for hosting logical service. In some embodiments, a particular one of the designated host machines hosts at least two DHCP services for two different logical networks as separate processes operating on the particular host machine.

Abstract: Some embodiments provide a method for managing a set of forwarding elements. The method receives configuration information for a set of gateways specifying (i) multiple gateways for implementing logical router ports and (ii) a ranking order of the gateways in the set. The method configures a first gateway in the ranking order as a master gateway for the set of gateways. Upon receiving a first notification that the first gateway is not operational, the method configures a second gateway in the ranking order as the master gateway for the set of gateways. Upon receiving a second, subsequent notification that the first gateway has resumed operation, the method maintains the second gateway in the ranking order as the master gateway for the set of gateways and configures the first gateway in the ranking order as a first standby gateway.