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Enabling FastResync on a volume

The recommended method for enabling FastResync on a volume with a version 20 DCO is to use the vxsnap prepare command.

See "Preparing a volume for DRL and instant snapshots" on page 284.

  Note   You need a FastResync 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 "Administering volume snapshots" on page 311.

See "FastResync" on page 66.

There are two possible versions of FastResync that can be enabled on a volume:

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.

  Note   It is not possible to configure both Persistent and Non-Persistent FastResync on a volume. Persistent FastResync is used if a DCO is associated with the volume. Otherwise, Non-Persistent FastResync is used.

To turn FastResync on for an existing volume, specify fastresync=on to the vxvol command as shown here:

# vxvol [-g diskgroup] set fastresync=on volume

To use FastResync with a snapshot, FastResync must be enabled before the snapshot is taken, and must remain enabled until after the snapback is completed.