Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for associating one or more of a plurality of metadata collections with one or more respective identifiers, wherein each metadata collection includes one or more pairings of metadata attributes with metadata values, and wherein each identifier is one of a project identifier, a tag identifier or an instance identifier; identifying, based on identifier information associated with a virtual machine instance, one or more metadata values to be provided to the virtual machine instance, wherein the identifier information specifies one or more of a project identifier, a tag identifier and an instance identifier, and wherein each identified metadata value belongs to a metadata collection associated with an identifier that is specified in the identifier information; and providing, to the virtual machine instance, the identified one or more metadata values.

Abstract: Techniques involving replication of storage are described. A representative technique includes apparatuses and methods for receiving replicated virtual storage of a replicated virtual machine, including at least a replicated base virtual disk that substantially corresponds to a primary base virtual disk to be replicated. Copies of differencing disks or other forms of virtual storage updates are received at a recovery site, each of the differencing disks being associated with the primary base virtual disk as descendents thereof. The received copies of the differencing disks are arranged relative to the replicated base virtual disk corresponding to the manner in which the differencing disks were arranged relative to the primary base virtual disk, thereby maintaining the data view of the replicated virtual machine in synchronization with the virtual machine at the primary site.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for maintaining virtual machine metadata. One of the methods includes initializing a first virtual machine (VM) on a first host machine using one or more elements of user-specified initialization metadata. Upon receiving a notification that the first VM has published one or more elements of VM-generated metadata, one or more elements of VM-generated metadata are obtained. A request is received for the one or more elements of VM-generated metadata, and the one or more elements of VM-generated metadata are provided in response to the request.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for associating one or more of a plurality of metadata collections with one or more respective identifiers, wherein each metadata collection includes one or more pairings of metadata attributes with metadata values, and wherein each identifier is one of a project identifier, a tag identifier or an instance identifier; identifying, based on identifier information associated with a virtual machine instance, one or more metadata values to be provided to the virtual machine instance, wherein the identifier information specifies one or more of a project identifier, a tag identifier and an instance identifier, and wherein each identified metadata value belongs to a metadata collection associated with an identifier that is specified in the identifier information; and providing, to the virtual machine instance, the identified one or more metadata values.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for associating one or more of a plurality of metadata collections with one or more respective identifiers, wherein each metadata collection includes one or more pairings of metadata attributes with metadata values, and wherein each identifier is one of a project identifier, a tag identifier or an instance identifier; identifying, based on identifier information associated with a virtual machine instance, one or more metadata values to be provided to the virtual machine instance, wherein the identifier information specifies one or more of a project identifier, a tag identifier and an instance identifier, and wherein each identified metadata value belongs to a metadata collection associated with an identifier that is specified in the identifier information; and providing, to the virtual machine instance, the identified one or more metadata values.

Abstract: A record of changes to virtual machine data of a virtual machine and a record of changes to snapshots of the virtual machine that have been received since the virtual machine was last backed up are maintained. In response to it being time to perform an incremental backup of the virtual machine, a portion of the virtual machine data is backed up based on the record of changes to the virtual machine data, and a portion of the snapshots is backed up based on the record of changes to the snapshots. In response to it being time to migrate the virtual machine to a second host device, the virtual machine data, the record of changes to the virtual machine data, the record of changes to the snapshots, and one or more of the snapshots are migrated to the second host device.

Abstract: Techniques involving replication of storage are described. A representative technique includes apparatuses and methods for receiving replicated virtual storage of a replicated virtual machine, including at least a replicated base virtual disk that substantially corresponds to a primary base virtual disk to be replicated. Copies of differencing disks or other forms of virtual storage updates are received at a recovery site, each of the differencing disks being associated with the primary base virtual disk as descendents thereof. The received copies of the differencing disks are arranged relative to the replicated base virtual disk corresponding to the manner in which the differencing disks were arranged relative to the primary base virtual disk, thereby maintaining the data view of the replicated virtual machine in synchronization with the virtual machine at the primary site.

Abstract: A record of changes to virtual machine data of a virtual machine and a record of changes to snapshots of the virtual machine that have been received since the virtual machine was last backed up are maintained. In response to it being time to perform an incremental backup of the virtual machine, a portion of the virtual machine data is backed up based on the record of changes to the virtual machine data, and a portion of the snapshots is backed up based on the record of changes to the snapshots. In response to it being time to migrate the virtual machine to a second host device, the virtual machine data, the record of changes to the virtual machine data, the record of changes to the snapshots, and one or more of the snapshots are migrated to the second host device.