I want to backup my laptop to a NAS drive using rsync. On both devices I have the same user and group. I'm using rsync with options: rltzuv. If I check the permissions on the NAS device I find the correct group setting but user is set to "500 - user #500". If I look into /etc/passwd user 500 is guest.
What can I do that ownership is set to the same user as on the laptop ?