Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

processing applications as it avoids the disk group split/join administrative step.
As with third-mirror break-off snapshots, you must wait for the contents of the
snapshot volume to be synchronized with the data volume before you can use the
vxsnap make command to take the snapshot.
When a link is created between a volume and the mirror that will become the
snapshot, separate link objects (similar to snap objects) are associated with the
volume and with its mirror. The link object for the original volume points to the
mirror volume, and the link object for the mirror volume points to the original
volume. All I/O is directed to both the original volume and its mirror, and a
synchronization of the mirror from the data in the original volume is started.
You can use the vxprint command to display the state of link objects, which
appear as type ln. Link objects can have the following states:
The mirror volume has been fully synchronized from the original
volume. The vxsnap make command can be run to create a snapshot.
ACTIVE
Synchronization of the mirror volume is in progress. The vxsnap
make command cannot be used to create a snapshot until the state
changes to ACTIVE. The vxsnap snapwait command can be used
to wait for the synchronization to complete.
ATTACHING
The mirror volume has been detached from the original volume
because of an I/O error or an unsuccessful attempt to grow the mirror
volume. The vxrecover command can be used to recover the mirror
volume in the same way as for a DISABLED volume.
See “Starting a volume” on page 314.
BROKEN
If you resize (grow or shrink) a volume, all its ACTIVE linked mirror volumes are
also resized at the same time. The volume and its mirrors can be in the same disk
group or in different disk groups. If the operation is successful, the volume and
its mirrors will have the same size.
If a volume has been grown, a resynchronization of the grown regions in its linked
mirror volumes is started, and the links remain in the ATTACHING state until
resynchronization is complete. The vxsnap snapwait command can be used to
wait for the state to become ACTIVE.
When you use the vxsnap make command to create the snapshot volume, this
removes the link, and establishes a snapshot relationship between the snapshot
volume and the original volume.
The vxsnap reattach operation re-establishes the link relationship between the
two volumes, and starts a resynchronization of the mirror volume.
See “Creating and managing linked break-off snapshot volumes” on page 378.
Administering volume snapshots
Linked break-off snapshot volumes
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