VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Chapter 8, Administering Volumes
Enabling FastResync on a Volume
207
As the volumesaremoved from the disk,thevxdiskadm programdisplays the status
of the operation:
Move volume voltest ...
Move volume voltest-bk00 ...
When the volumes have all been moved, the vxdiskadm program displays the
following success message:
Evacuation of disk disk01 is complete.
3. At the following prompt, indicate whether you want to move volumes from another
disk (y) or return to the vxdiskadm main menu (n):
Move volumes from another disk? [y,n,q,?] (default: n)
Enabling FastResync on a Volume
Note You may need an additional license to use this feature.
FastResync performs quick and efficient resynchronization of stale mirrors. It also
increases the efficiency of the VxVM snapshot mechanism when used with operations
such as backup and decision support. See “BackingUp Volumes Online Using Snapshots”
on page 214 and “FastResync” on page 43 for more information.
From Release 3.2, there are two possible versions of FastResync that can be enabled on a
volume:
◆ Persistent FastResync, introduced in VxVM 3.2, holds copies of the FastResync maps
on disk. These can be used for the speedy recovery of mirrored volumes if a system is
rebooted. This form of FastResync requires that both a data change object (DCO) and
DCO volume first be associated with the volume.
See “Creating a Volume with a DCO and DCO Volume” on page 171, and “Adding a
DCO and DCO Volume” on page 193 for more information.
If theexisting volume was createdbefore release 3.2of VxVM, and it hasany attached
snapshot plexes or it is associated with any snapshot volumes, follow the procedure
given in “Enabling Persistent FastResync on Existing Volumes with Associated
Snapshots” on page 209.
◆ Non-Persistent FastResync, introduced in VxVM 3.1, holds the FastResync maps in
memory. These do not survive on a system that is rebooted.
By default, FastResync is not enabled on newly created volumes. Specify the
fastresync=on attribute to the vxassist make command if you want to enable
FastResync on a volume that you are creating.