Creates a new volume by taking one or more attached temporary mirrors (with state SNAPDONE) to use as its plexes.
The nmirror= number attribute can be used to specify the number of mirrors in a snapshot volume. At least number SNAPDONE plexes must be available in the original volume. By default, one plex is used if nmirrors is not specified. The comment attribute may also be used to set the comment field for the snapshot volume.
The following are examples of the use of the nmirror and comment attributes:
# vxassist snapshot nmirror=2 comment=”mirrored snapvol for myvol” myvol snapvol
- If the fsgen usage type is used with a volume containing a Veritas File System (VxFS), some times the command will attempt to synchronize any in-memory data associated with the volume (such as unwritten file system modifications) when the snapshot operation is done.
- For ufs and s5, the synchronization operation calls sync. This makes the snapshot a better image, but it may leave some inconsistencies between in-memory file system data and the data residing on the backup image.
- The snapshot command accepts more than one volume. All the given volumes are split atomically (in a single transaction). That is, all the given volumes are relatively consistent as a result of taking the snapshot.
- If you specify the -o allvols, it is not necessary to specify any volume names. vxassist attempts to create a sufficiently long vxplex command to take a snapshot of all the volumes in the disk group.
- The option -o name= pattern used to generate names for the snapshot volumes. Otherwise, the default name assigned to each snapshot volume takes the form SNAP%d-%v.