Using replication in a storage pool
To enable data replication in a storage pool, you must make certain that there are at least two failure groups within the storage pool.
This is necessary because GPFS maintains
separation between storage pools and performs file replication within
each storage pool. In other words, a file and its replica must be
in the same storage pool. This also means that if you are going to
replicate the entire file system, every storage pool in the file system
must have at least two failure groups.
Note: Depending on the configuration
of your file system, if you try to enable file replication in a storage
pool having only one failure group, GPFS will
either give you a warning or an error message.