Does anyone here know how to mirror Hammer2?
https://www.dragonflybsd.org/docs/how_to_implement_hammer_pseudo_file_system40pfs41_slave_mirroring_from_pfs_master/
For HAMMER2, the feature is still missing, unlike for the older HAMMER. The closest workaround is to use the 'cpdup' program, which duplicates what is in one location to another.