https://forums.freenas.org/index.php?threads/replication-dataset-set-a-read-only.46889/

https://forums.freenas.org/index.php?threads/replication-target-datasets-mounted-ro-in-freenas-9-3-stable-201602020212-and-newer.41246/

https://forums.freenas.org/index.php?threads/zfs-replication-and-making-the-destination-read-write.10551/

https://bugs.freenas.org/issues/15011

zfs list -o name,mountpoint,mounted,readonly volrep/common

zfs set readonly=off tank/root