Distributed Virtual Switch for Virtualized Computer Systems

• US 20090292858A1
• Filed: 05/23/2008
• Published: 11/26/2009
• Est. Priority Date: 05/23/2008
• Status: Active Grant

• Current Assignee: Vmware LLC (Broadcom, Inc.)
• Original Assignee: VMware, Inc. (Broadcom, Inc.)
• Inventors: Zhou, Shudong, Lambeth, Andrew
• Granted Patent: US 8,195,774 B2
• Time in Patent Office: Days
• US Class Current: 711/6
• CPC Class Codes: G06F 2009/4557 Distribution of virtual machine instances; Migration and load balancing
• CPC Class Codes: G06F 2009/45575 Starting, stopping, suspending or resuming virtual machine instances
• CPC Class Codes: G06F 2009/45579 I/O management, e.g. providing access to device drivers or storage
• CPC Class Codes: G06F 2009/45595 Network integration; Enabling network access in virtual machine instances
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: H04L 2101/622 Layer-2 addresses, e.g. medium access control [MAC] addresses
• CPC Class Codes: H04L 49/70 Virtual switches

Abstract

A method for persisting a state of a virtual port in a virtualized computer system is described. A distributed virtual port (DVport) is stored in a persistent storage location, the DVport comprising a state of a corresponding virtual port and configuration settings of the virtual port. In addition, an association between the virtual port and the virtual network interface card (VNIC) connected to the virtual port is stored. When a virtual machine corresponding to the VNIC is restarted, the state from the DVport is restored to a new virtual port from the persistent storage location.

Claims

1. A method for persisting a state of a virtual port in a virtualized computer system having at least one virtual machine, virtualization software logically interposed between the virtual machines and system hardware, each virtual machine including a guest operating system and at least one virtual network interface card (VNIC), the virtualization software implementing the VNIC using emulation software and a virtual switch, the virtual switch comprising a virtual port corresponding to each of the VNICs, the virtual switch functioning to forward network frames between the VNICs and zero or more physical network interface cards (NICs) connected to the system hardware, the method comprising:

storing a distributed virtual port (DVport) in a persistent storage location, the DVport comprising a runtime state and configuration settings;

storing an association between the DVport and the VNIC connected to the DVport; and

restoring a state from the DVport to a new virtual port from the persistent storage location when the VM corresponding to the connected VNIC is restarted.

2. The method of claim 1, wherein the DVport further comprises a unique connection identifier (ID) and the storing of the association between the DVport and the VNIC comprises storing the connection ID along with VNIC state when the virtual machine is shut down or suspended.

3. The method of claim 1, wherein:

the virtualized computer system is one of a managed collection of hosts; and

the VM is shut down or suspended on one host and subsequently restarted on a host different from the one host.

4. The method of claim 1, wherein:

the virtualized computer system is one of a managed collection of hosts; and

a collection of the virtual ports for the collection hosts form a distributed virtual switch.

5. The method of claim 4, wherein the distributed virtual switch is managed as an abstraction of a physical switch that is connected to each of the VMs running on the collection of hosts that are connected to a physical local area network (LAN).

6. The method of claim 1, wherein the persistent storage location includes a database maintained on a separate server.

7. The method of claim 6, wherein the separate server is accessed via a network independent of the VNICs.

8. The method of claim 1, wherein a collection of DVports forms a distributed virtual switch, the method further comprising attaching a VM to a virtual switch by:

transmitting a request for a connection to a DVport from the VNIC of the VM to a database controller responsible for managing the distributed virtual switch;

determining that the DVport is currently unassigned to another VNIC, and initializing the DVport to an initial state and default configuration;

generating a new connection ID corresponding to the DVport in response to the request and transmitting the new connection ID to the VNIC;

passing the initialized state and default configuration of the DVport to the virtual port that backs up the DVport, so that the virtual port assumes the state and configuration of the DVport;

transmitting a request from the VNIC to system level software of the virtualized computer system to back the DVport with a virtual port, the system level software responding to the request by associating the DVport with a virtual port of the virtual switch; and

linking the virtual port configured to back up the DVport with the VNIC to which the DVport is assigned so that the VNIC and virtual switch can exchange network frames.

9. The method of claim 8, wherein the database controller resides on a server computer that is separate from virtualized computer system.

10. The method of claim 1, wherein a collection of DVports forms a distributed virtual switch and the restoring of the state comprises:

transmitting a connection ID of a DVport to a database controller responsible for managing the distributed virtual switch;

determining that the VM is assigned to the DVport and correspondingly transmitting a state and configuration of the DVport to the VM;

assigning a virtual port to backup the DVport assigned to the VM and causing the virtual port to assume the state and configuration of the DVport; and

linking the virtual port with the VNIC to which the DVport is assigned so that the VNIC and virtual switch can exchange network frames.

11. The method of claim 1, further comprising:

modifying the configuration of the DVport; and

causing the modification of the DVport to take effect immediately regardless of the DVport host location and running state.

12. A tangible medium embodying machine readable instructions causing a computer to perform a method for persisting a state of a virtual port in a virtualized computer system having at least one virtual machine, virtualization software logically interposed between the virtual machines and system hardware, each virtual machine including a guest operating system and at least one virtual network interface card (VNIC), the virtualization software implementing the VNIC using emulation software and a virtual switch, the virtual switch comprising a virtual port corresponding to each of the VNICs, the virtual switch functioning to forward network frames between the VNICs and zero or more physical network interface cards (NICs) connected to the system hardware, the method comprising:

storing a distributed virtual port (DVport) in a persistent storage location, the DVport comprising a runtime state and configuration settings;

storing an association between the DVport and the VNIC connected to the DVport; and

restoring a state from the DVport to a new virtual port from the persistent storage location when the VM corresponding to the connected VNIC is restarted.

13. The tangible medium of claim 12, wherein the DVport further comprises a unique connection identifier (ID) and the storing of the association between the DVport and the VNIC comprises storing the connection ID along with VNIC state when the virtual machine is shut down or suspended.

14. The tangible medium of claim 12, wherein:

the virtualized computer system is one of a managed collection of hosts; and

the VM is shut down or suspended on one host and subsequently restarted on a host different from the one host.

15. The tangible medium of claim 12, wherein:

the virtualized computer system is one of a managed collection of hosts; and

a collection of the virtual ports for the collection hosts form a distributed virtual switch.

16. The tangible medium of claim 15, wherein the distributed virtual switch is managed as an abstraction of a physical switch that is connected to each of the VMs running on the collection of hosts that are connected to a physical local area network (LAN).

17. The tangible medium of claim 12, wherein the persistent storage location includes a database maintained on a separate server.

18. The tangible medium of claim 17, wherein the separate server is accessed via a network independent of the VNICs.

19. The tangible medium of claim 12, wherein a collection of DVports forms a distributed virtual switch, the method further comprising attaching a VM to a virtual switch by:

transmitting a request for a connection to a DVport from the VNIC of the VM to a database controller responsible for managing the distributed virtual switch;

determining that the DVport is currently unassigned to another VNIC, and initializing the DVport to an initial state and default configuration;

generating a new connection ID corresponding to the DVport in response to the request and transmitting the new connection ID to the VNIC;

passing the initialized state and default configuration of the DVport to the virtual port that backs up the DVport, so that the virtual port assumes the state and configuration of the DVport;

transmitting a request from the VNIC to system level software of the virtualized computer system to back the DVport with a virtual port, the system level software responding to the request by associating the DVport with a virtual port of the virtual switch; and

linking the virtual port configured to back up the DVport with the VNIC to which the DVport is assigned so that the VNIC and virtual switch can exchange network frames.

20. The tangible medium of claim 19, wherein the database controller resides on a server computer that is separate from virtualized computer system.

21. The tangible medium of claim 12, wherein a collection of DVports forms a distributed virtual switch and the restoring of the state comprises:

transmitting a connection ID of a DVport to a database controller responsible for managing the distributed virtual switch;

determining that the VM is assigned to the DVport and correspondingly transmitting a state and configuration of the DVport to the VM;

assigning a virtual port to backup the DVport assigned to the VM and causing the virtual port to assume the state and configuration of the DVport; and

linking the virtual port with the VNIC to which the DVport is assigned so that the VNIC and virtual switch can exchange network frames.

22. The tangible medium of claim 12, the method further comprising:

modifying the configuration of the DVport; and

causing the modification of the DVport to take effect immediately regardless of the DVport host location and running state.