With Windows Server 2012 R2, Linux virtual machines can be backed up in the same manner as virtual machines running Windows. Supported Linux operating systems with updated integration services components appear in the list of available virtual machines when backing up a server running Hyper-V.
Hyper-V provides the ability for backup programs to backup Windows virtual machines in a data consistent fashion without disrupting the tenant workload inside the virtual machine. Backup of Linux virtual machines should have the same experience as Windows virtual machines.
Linux does not have a VSS like framework to co-ordinate with applications and to move them into a consistent state. It has utilities (e.g. fsfreeze) to flush the File System cache and metadata updates and freeze all I/O to the file system. This mechanism provides a way to achieve a file system consistent state.
The Linux IC will put the file system into a consistent state. The file system will freeze until it is further instructed to thaw. We use the term “application consistency” to refer to file system consistency for Linux guests. This will act in place of the freeze/thaw that VSS is used to.