Abstract: A system and method for assigning virtual machines to network interfaces. A first virtual machine is assigned to a network interface according to a first rule and a second virtual machine is assigned to a network interface according to a second rule. The assignment rules are dependent on network conditions as determined through at least one of the network interfaces. The first rule and the second rule may specify assignments differently, such that the same network conditions may result in different assignments for the first and second virtual machines.

Abstract: A virtual computer system enabling dynamic, aggregated use of multiple TCP/IP offload engines (TOEs) by the set of guest computer systems hosted on the virtual computer system. Each of the guest computer systems includes an offload selection switch and the associated virtual machine monitor includes a first virtual context component. Second virtual context components are associated with a set of TCP/IP stacks and TOEs and interoperate with the first virtual context components to establish a virtual routing of network connections between the offload selection switches and the TOEs. The virtual context mapping retains the initially requested network connection information as well as the resolved virtual network connection established, thereby allowing the initial network connection request to be internally reapplied as required to accommodate dynamic changes in the network protocol parameters of the TOEs.

Abstract: An embodiment of the present invention is directed to a method of determining a probable IP subnet of a network. The method includes maintaining a table of possible networks. The entries of the table include respective network addresses, respective subnet masks, and respective scores. The method also includes observing a packet, determining an IP address of the packet, and comparing the IP address of the packet with the respective network addresses of the entries of the table of possible networks. If the IP address of the packet falls under the respective network address of a particular entry, the respective score of the particular entry is adjusted. Otherwise, a new entry is created in the table of possible networks corresponding to the IP address of the packet. The method also includes ranking the entries of the table of possible networks based on their respective scores.

Abstract: A virtual device emulated in software and included in a virtual machine is provided in a virtualized computer system. The virtual device includes an emulation mode and a pass through mode. The emulation mode is used for a first plurality of device operations. The pass through mode is used for a second plurality of device operations. The virtual device is configured to communicate with a physical device and each of the second plurality of device operations are configured to be handled by the physical device. The virtual device also includes a switching logic to switch between the emulation mode and the pass through mode based on a device operation to be performed by the virtual machine of the virtual device.

Abstract: Methods and systems for implementing private allocated networks in a virtual infrastructure are presented. One method operation creates virtual switches in one or more hosts in the virtual infrastructure. Each port in the virtual switches is associated with a private allocated network (PAN) from a group of possible PANs. In one embodiment, one or more PANs share the same physical media for data transmission. The intranet traffic within each PAN is not visible to nodes that are not connected to the each PAN. In another operation, the method defines addressing mode tables for the intranet traffic within each PAN. The entries in the addressing mode tables define addressing functions for routing the intranet traffic between the virtual switches, and different types of addressing functions are supported by the virtual switches.

Abstract: Methods, systems and computer programs for migrating a virtual machine (VM) executing on a first host to a second host are presented, where the first host and the second are on different networks. One embodiment of a method includes assigning to the VM a VM address (VMA) belonging to a VM network and publishing a first route to an associated network (AN) via a first virtual router executing on the first host. The method further includes migrating the VM from the first host to the second host, the VM maintaining the assigned VMA after migrating, and publishing a second route to the AN via a second virtual router executing on the second host. The first and second virtual routers have addresses belonging to the VM network, and network packets to and from the VM flow through the virtual router where the VM is executing. A temporary tunnel between the virtual routers allows traffic to flow to the VM while the new route to AN is propagated throughout the network.

Abstract: In a virtualized computer system, a network frame is transmitted from a virtual machine using a network interface device, possibly through a virtual switch, by copying only a part of the network frame to the transmit buffers that have pre-translated mappings from guest physical addresses to hypervisor virtual addresses and to machine addresses. The length of the part of the network frame that is copied to the transmit buffers may be variable.

Abstract: In a virtualized computer system, a network frame is transmitted from a virtual machine using a network interface device, possibly through a virtual switch, by copying only a part of the network frame to the transmit buffers that have pre-translated mappings from guest physical addresses to hypervisor virtual addresses and to machine addresses. The length of the part of the network frame that is copied to the transmit buffers may be variable.

Abstract: In a virtualized computer system, a network frame is transmitted from a virtual machine using a network interface device, possibly through a virtual switch, by copying only a part of the network frame to the transmit buffers that have pre-translated mappings from guest physical addresses to hypervisor virtual addresses and to machine addresses. The length of the part of the network frame that is copied to the transmit buffers may be variable.

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.

Abstract: A virtual device emulated in software and included in a virtual machine is provided in a virtualized computer system. The virtual device includes an emulation mode and a pass through mode. The emulation mode is used for a first plurality of device operations. The pass through mode is used for a second plurality of device operations. The virtual device is configured to communicate with a physical device and each of the second plurality of device operations are configured to be handled by the physical device. The virtual device also includes a switching logic to switch between the emulation mode and the pass through mode based on a device operation to be performed by the virtual machine of the virtual device.

Abstract: A system and method for maintaining processing order while permitting parallelism. Processing of a piece of work is divided into a plurality of stages. At each stage, a task advancing the work towards completion is performed. By performing processing as a sequence of tasks, processing can be done in parallel, with progress being made simultaneously on different pieces of work in different stages by a plurality of threads of execution.