Comparison of snapshot features

Table: Comparison of snapshot features for supported snapshot types compares the features of the various types of snapshots that are supported in VxVM.

Table: Comparison of snapshot features for supported snapshot types

Snapshot feature

Full-sized instant (vxsnap)

Space-optimized instant (vxsnap)

Break-off (vxassist or vxsnap)

Immediately available for use on creation

Yes

Yes

No

Requires less storage space than original volume

No

Yes

No

Can be reattached to original volume

Yes

No

Yes

Can be used to restore contents of original volume

Yes

Yes

Yes

Can quickly be refreshed without being reattached

Yes

Yes

No

Snapshot hierarchy can be split

Yes

No

No

Can be moved into separate disk group from original volume

Yes

No

Yes

Can be turned into an independent volume

Yes

No

Yes

FastResync ability persists across system reboots or cluster restarts

Yes

Yes

Yes

Synchronization can be controlled

Yes

No

No

Can be moved off-host

Yes

No

Yes

Full-sized instant snapshots are easier to configure and offer more flexibility of use than do traditional third-mirror break-off snapshots. For preference, new volumes should be configured to use snapshots that have been created using the vxsnap command rather than using the vxassist command. Legacy volumes can also be reconfigured to use vxsnap snapshots, but this requires rewriting of administration scripts that assume the vxassist snapshot model.