The cmirror packages provide user-level utilities for managing cluster mirroring.
Due to limitations in the cluster infrastructure, cluster mirrors greater than 1.5TB cannot be created with the default region size. If larger mirrors are required, the region size should be increased from its default (512kB), for example:
# -R <region_size_in_MiB>
lvcreate -m1 -L 2T -R 2 -n mirror vol_group
Failure to increase the region size will result in the LVM creation process hanging and may cause other LVM commands to hang. (BZ#514814)