ZFS should let the user specify or modify the mount_dev of a dataset
Review Request #105 - Created Oct. 19, 2015 and discarded
If we need to migrate a zfs pool with filesystem exported through NFS, we'd like to keep the fh3_fsid the same across when migrating the filesystem over to a new system.
One way to do this is to configure the same mount_dev as a filesystem property. A different system that will import the same pool will then attempt to use the configured mount_dev, thus keeping a fixed fh3_fsid.
1. that the mounted devices has the specified dev= after mount.
2. snooped NFS traffic to confirm that the fh3_fsid is the one configured.