Hi Jáder
Create a new group eg mother-users.
Put all users on the "mother" system into that group.
Give that group access to what it needs.
You can do the same with "son" users (but since there are only two it may not be worthwhile).
Create a group son-users and put all users of the "son" system into that group.
Give that group access to what it needs.
This WILL survive a reboot - AND a Restore.
AND- if you had a backup server running AFFA, it would survive a "RISE" operation on the backup server.
Only give "everyone" access permission to something you really do want everyone to be able to see.....or modify/delete if that's what you want. Use it sparingly and carefully. It should not be your all-in, one-size-fits-all, standard solution for access.
Cheers and good luck.
Ian