chlvcopy {-B | -b{-c copy]} [-f} LV name
Note: To use this command, you must either have root user authority or be a member of the system group.
All partitions of a logical volume must be fresh before chvlcopy can mark a mirror copy as a readonly backup. Only a single copy may be marked as a backup mirror. If a copy is already marked, then the command will fail if a different copy is specified.
Although the chlvcopy command can mark readonly copies on logical volumes that are open (including logical volumes containing mounted file systems), this is not recommended unless the application is at a known state at the time the copy is marked as a backup. The backup copy is internally consistent at the time the chlvcopy command is run, but consistency is lost between the logical volume and the backup mirror copy if the logical volume is accessed by multiple processes simultaneously and the application is not at a known state. When marking an open logical volume, data may be lost or corrupted. Logical volumes should be closed before marking readonly mirror copies in order to avoid a potential corruption window.
If a volume group is taken offline or if the machine crashes, the existence of the backup mirror is lost. To prevent the loss of backup data, the volume group should be set to not automatically varyon and the -n flag should be used with varyonvg to prevent stale partitions from being resynced. The chlvcopy command can be run again to continue with the backup.
If the volume group is varied on in concurrent mode then the chlvcopy command will fail.
The readlvcopy command.