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 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 a network controller that manages multiple managed forwarding elements (MFEs) that implement multiple logical networks. The method stores (i) a first data structure including an entry for each logical entity in a desired state of the multiple logical networks and (ii) a second data structure including an entry for each logical entity referred to by an update for at least one MFE. Upon receiving updates specifying modifications to the logical entities, the method adds separate updates to separate queues for the MFEs that require the update. The separate updates reference the logical entity entries in the second data structure. When the second data structure reaches a threshold size in comparison to the first data structure, the method compacts the updates in at least one of the queues so that each queue has no more than one update referencing a particular logical entity entry.

Abstract: A novel method for managing firewall configuration of a software defined data center is provided. Such a firewall configuration is divided into multiple sections that each contains a set of firewall rules. Each tenant of the software defined data center has a corresponding set of sections in the firewall configuration. The method allows each tenant to independently access and update/manage its own corresponding set of sections. Multiple tenants or users are allowed to make changes to the firewall configuration simultaneously.

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

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

Abstract: Disclosed is a technique for communicating message objects from a first process to a second process in transport node of a virtualized network, the message objects specifying a change to status of a virtualized network object in the virtualized network. In technique, message objects are separated from operation objects, which have fields corresponding to the fields of the message objects, a field of the operations object being capable of specifying a change to or a status of a field of the message object to which it corresponds. Yet another object combines a message object and an operation object so that the protocol for communication between the first and second process is the same regardless of the contents of the actual message.

Abstract: A novel method for distributing firewall configuration of a software defined data center is provided. The network manager of the data center receives update requests from tenants of the data center and correspondingly generates update fragments and delivers the generated update fragment to local control planes controlling the enforcing devices. Each local control plane in turn integrates the update fragments it receives into its firewall rules table. For each rule and/or section thusly integrated, the local control plane uses the rule or the section's assigned priority number to establish ordering in the firewall rules table of the local control plane.

Abstract: Some embodiments provide a method for a network controller that manages multiple managed forwarding elements (MFEs) that implement multiple logical networks. The method stores (i) a first data structure including an entry for each logical entity in a desired state of the multiple logical networks and (ii) a second data structure including an entry for each logical entity referred to by an update for at least one MFE. Upon receiving updates specifying modifications to the logical entities, the method adds separate updates to separate queues for the MFEs that require the update. The separate updates reference the logical entity entries in the second data structure. When the second data structure reaches a threshold size in comparison to the first data structure, the method compacts the updates in at least one of the queues so that each queue has no more than one update referencing a particular logical entity entry.

Abstract: Some embodiments provide a method for a network controller that manages multiple managed forwarding elements (MFEs) that implement multiple logical networks. The method stores (i) a first data structure including an entry for each logical entity in a desired state of the multiple logical networks and (ii) a second data structure including an entry for each logical entity referred to by an update for at least one MFE. Upon receiving updates specifying modifications to the logical entities, the method adds separate updates to separate queues for the MFEs that require the update. The separate updates reference the logical entity entries in the second data structure. When the second data structure reaches a threshold size in comparison to the first data structure, the method compacts the updates in at least one of the queues so that each queue has no more than one update referencing a particular logical entity entry.

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 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 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 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: 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 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 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.

Abstract: The present disclosure generally relates to an encoding scheme, and more specifically to a stable encoding scheme that is both variable-length and order-preserving. The present disclosure further describes a decoding scheme to decode and encoding generated by the encoding scheme. The encoding scheme may be parameterized by a single parameter k which remains constant across encoding and corresponding decoding operations. The output encodings generated by the encoding scheme are variable-length while maintaining order.

Abstract: Disclosed is a technique for communicating message objects from a first process to a second process in transport node of a virtualized network, the message objects specifying a change to status of a virtualized network object in the virtualized network. In technique, message objects are separated from operation objects, which have fields corresponding to the fields of the message objects, a field of the operations object being capable of specifying a change to or a status of a field of the message object to which it corresponds. Yet another object combines a message object and an operation object so that the protocol for communication between the first and second process is the same regardless of the contents of the actual message.