Description of problem:
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Gluster geo-replication for security reasons makes the slave volume read-only once the gluster geo-replication session is created and synced.

So before importing the gluster slave volume as a storage domain, one need to make that volume RW, for the RHV to import the storage domain.
This can be done by:
# gluster volume set <slave-vol> features.read-only off

This content should go in 2 places of restoring in Chapter-13

1. Section 13.1.1, after point-1
2. Section 13.2

Expected results:
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Add content to allow RW on the slave volume, before restoring/importing gluster volume as storage domain