The procedure described in this section describes how to upgrade a volume created using a version older than VxVM 5.0 so that it can take advantage of database FlashSnap.
Note The plexes of the DCO volume require persistent storage space on disk to be available. To make room for the DCO plexes, you may need to add extra disks to the disk group, or reconfigure existing volumes to free up space in the disk group. Another way to add disk space is to use the disk group move feature to bring in spare disks from a different disk group.
Note Existing snapshot volumes created by the vxassist command are not supported. A combination of snapshot volumes created by vxassist and vxsnap are not supported.
To upgrade an existing volume created with an earlier version of VxVM
To upgrade a disk group to the latest version, use the following command:
# vxassist [-g diskgroup] remove log volume [nlog=n]
Use the optional attribute nlog=n to specify the number, n, of logs to be removed. By default, the vxassist command removes one log.
# vxsnap [-g diskgroup] snapback snapvol
If persistent FastResync was enabled on the volume before the snapshot was taken, the data in the snapshot plexes is quickly resynchronized from the original volume. If persistent FastResync was not enabled, a full resynchronization is performed.
# vxsnap [-g diskgroup] prepare volume
Provide two disk names to avoid overlapping the storage of the snapshot DCO plex with any other non-moving data or DCO plexes.
The vxsnap prepare command automatically enables persistent FastResync on the volume and on any snapshots that are generated from it. It also associates a DCO and DCO log volume with the volume to be snapshot.
# vxsnap [-g diskgroup] addmir dco_volume_name
where dco_volume_name is the name of the DCO volume you are creating.
# vxplex [-g diskgroup] -o dcoplex=dco_plex_name convert \
where dco_plex_name is the name of the DCO plex you are creating.
In this example, the volume, data_vol, is upgraded to make use of VxVM 5.0 features.
# vxsnap -g PRODdg prepare data_vol alloc="PRODdg01 PRODdg02"
In this scenario, there are enough DCO plexes for the data plexes. Also, no data plex is associated with a DCO plex.
v data_vol fsgen ENABLED 4194304 - ACTIVE - -
pl data_vol-01 data_vol ENABLED 4194304 - ACTIVE - -
sd PRODdg01-01 data_vol-01 ENABLED 4194304 0 - - -
pl data_vol-04 data_vol ENABLED 4194304 - SNAPDONE - -
sd PRODdg02-03 data_vol-04 ENABLED 4194304 0 - - -
dc data_vol_dco data_vol - - - - - -
v data_vol_dcl gen ENABLED 560 - ACTIVE - -
pl data_vol_dcl-01 data_vol_dcl ENABLED 560 - ACTIVE - -
sd PRODdg01-02 data_vol_dcl-01 ENABLED 560 0 - - -
pl data_vol_dcl-02 data_vol_dcl ENABLED 560 - ACTIVE - -
sd PRODdg02-02 data_vol_dcl-02 ENABLED 560 0 - - -
# vxplex -g PRODdg -o dcoplex=data_vol_dcl-02 \
convert state=SNAPDONE data_vol-04
pl data_vol-03 - DISABLED 4194304 - - - -
sd PRODdg02-01 data_vol-03 ENABLED 4194304 0 - - -
v data_vol fsgen ENABLED 4194304 - ACTIVE - -
pl data_vol-01 data_vol ENABLED 4194304 - ACTIVE - -
sd PRODdg01-01 data_vol-01 ENABLED 4194304 0 - - -
pl data_vol-04 data_vol ENABLED 4194304 - SNAPDONE - -
sd PRODdg02-03 data_vol-04 ENABLED 4194304 0 - - -
dc data_vol_dco data_vol - - - - - -
v data_vol_dcl gen ENABLED 560 - ACTIVE - -
pl data_vol_dcl-01 data_vol_dcl ENABLED 560 - ACTIVE - -
sd PRODdg01-02 data_vol_dcl-01 ENABLED 560 0 - - -
pl data_vol_dcl-02 data_vol_dcl DISABLED 560 - DCOSNP - -
sd PRODdg02-02 data_vol_dcl-02 ENABLED 560 0 - - -
In this scenario, there are fewer DCO plexes than data plexes.
pl data_vol-03 - DISABLED 4194304 - - - -
sd PRODdg02-01 data_vol-03 ENABLED 4194304 0 - - -
v data_vol fsgen ENABLED 4194304 - ACTIVE - -
pl data_vol-01 data_vol ENABLED 4194304 - ACTIVE - -
sd PRODdg01-01 data_vol-01 ENABLED 4194304 0 - - -
pl data_vol-04 data_vol ENABLED 4194304 - ACTIVE - -
sd PRODdg02-03 data_vol-04 ENABLED 4194304 0 - - -
dc data_vol_dco data_vol - - - - - -
v data_vol_dcl gen ENABLED 560 - ACTIVE - -
# vxplex -g PRODdg -o dcoplex=data_vol_dcl-02 \
convert state=SNAPDONE data_vol-04
pl data_vol-03 - DISABLED 4194304 - - - -
v data_vol fsgen ENABLED 4194304 - ACTIVE - -
pl data_vol-01 data_vol ENABLED 4194304 - ACTIVE - -
sd PRODdg01-01 data_vol-01 ENABLED 4194304 0 - - -
pl data_vol-04 data_vol ENABLED 4194304 - SNAPDONE - -
sd PRODdg02-03 data_vol-04 ENABLED 4194304 0 - - -
dc data_vol_dco data_vol - - - - - -
v data_vol_dcl gen ENABLED 560 - ACTIVE - -
pl data_vol_dcl-01 data_vol_dcl ENABLED 560 - ACTIVE - -
sd PRODdg01-02 data_vol_dcl-01 ENABLED 560 0 - - -