HP Veritas Volume Manager 5.0 -UX 11i v3 manual Displaying instant snapshot information

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Administering volume snapshots

Creating instant snapshots

Note: The topmost snapshot volume in the hierarchy must have been fully synchronized for this command to succeed. Snapshots that are lower down in the hierarchy need not have been fully resynchronized. See “Controlling instant snapshot synchronization” on page 344 for more information.

The following command splits the snapshot hierarchy under snap2myvol from its parent volume:

#vxsnap -g mydg split snap2myvol

Note: When applied to a volume set or to a component volume of a volume set, this operation can result in inconsistencies in the snapshot hierarchy in the case of a system crash or hardware failure. If the operation is applied to a volume set, the -f(force) option must be specified.

Displaying instant snapshot information

The vxsnap print command may be used to display information about the snapshots that are associated with a volume.

#vxsnap [-g diskgroup] print [vol]

This command shows the percentage progress of the synchronization of a snapshot or volume. If no volume is specified, information about the snapshots for all the volumes in a disk group is displayed. The following example shows a volume, vol1, which has a full-sized snapshot, snapvol1 whose contents have not been synchronized with vol1:

#vxsnap -g mydg print

NAME	SNAPOBJECT	TYPE	PARENT	SNAPSHOT	%DIRTY	%VALID
vol1	--	volume	--	--	--	100
	snapvol1_snp1volume		--	snapvol1	1.30	--
snapvol1	vol1_snp1	volume	vol1	--	1.30	1.30

The %DIRTY value for snapvol1 shows that its contents have changed by 1.30% when compared with the contents of vol1. As snapvol1 has not been synchronized with vol1, the %VALID value is the same as the %DIRTY value. If the snapshot were partly synchronized, the %VALID value would lie between the %DIRTY value and 100%. If the snapshot were fully synchronized, the %VALID value would be 100%. The snapshot could then be made independent or moved into another disk group.

Additional information about the snapshots of volumes and volume sets can be obtained by using the -noption with the vxsnap print command:

# vxsnap [-g diskgroup] -n [-l] [-v] [-x] print [vol]