Abstract: An active-active storage system includes a first storage device and a second storage device. The first storage device receives data of a first file sent by a client cluster to a file system, stores the data of the first file, and sends a first copy of the data of the first file to the second storage device. The second storage device receives data of a second file sent by the client cluster to the file system, stores the data of the second file, and sends a second copy of the data of the second file to the first storage device.

Abstract: A method for determining virtual machine migration relates to the field of communications and can reduce a deployment cost. The method includes a client in a host machine obtains a unique identifier of a virtual machine on the host machine and an address of the host machine; and if the unique identifier of the virtual machine does not exist in a local record of the client, the client sends a packet to a server in a network in which the host machine is located, where the packet carries the unique identifier of the virtual machine and the address of the host machine, so that the server determines, according to the unique identifier of the virtual machine and the address of the host machine, whether the virtual machine is migrated; and the client adds the unique identifier of the virtual machine to the local record to update the local record.

Abstract: A method for determining virtual machine migration relates to the field of communications and can reduce a deployment cost. The method includes a client in a host machine obtains a unique identifier of a virtual machine on the host machine and an address of the host machine; and if the unique identifier of the virtual machine does not exist in a local record of the client, the client sends a packet to a server in a network in which the host machine is located, where the packet carries the unique identifier of the virtual machine and the address of the host machine, so that the server determines, according to the unique identifier of the virtual machine and the address of the host machine, whether the virtual machine is migrated; and the client adds the unique identifier of the virtual machine to the local record to update the local record.

Abstract: The present invention provides a network communication method and device. The method includes: receiving, by a VNC on a physical host, a network communication packet sent by a first virtual machine of which a host machine is the physical host and which has a mapping relationship with the VNC, where a source address carried in the network communication packet is an address of the first virtual machine, a destination address carried in the network communication packet is an address of a second virtual machine or an address of another physical host; selecting, by the physical host, a VPN network corresponding to the VNC on the physical host according to preset correspondence between the VPN network and the VNC; and sending, by the physical host, the network communication packet through the selected VPN network. The present invention lowers the restriction on setting an IP address of a virtual machine in a VPN.

Abstract: In one aspect, the present invention provides methods for generating doubled haploid and/or haploid maize plants from microspores. The methods of this aspect of the invention include the steps of: (a) selecting maize plant material comprising maize microspores at a developmental stage amenable to androgenic induction; (b) incubating the microspores in incubation medium at a temperature and osmolarity effective to induce androgenesis to obtain temperature-treated microspores; (c) isolating the temperature-treated microspores; (d) cultivating the isolated, temperature-treated microspores in cultivation medium with either at least one live plant ovary and/or ovary-conditioned medium to produce regenerative maize tissue, wherein the cultivation medium has an osmolarity between about 300 mOsm and about 500 mOsm and comprises at least one cytokinin and at least one auxin; and (e) regenerating maize plants from the regenerative maize tissue.