Say I have a user with UID 500 on a linux machine for administration purposes. This machine is a backup repository for other *nix machines.
I need the user 500 to access the files in the backups, but the files are owned by other UIDs that don't exist on the local machine (e.g UID 1000).
Is there a way to allow the user with UID 500 to access the files that are owned by UID 1000 ? I searched if there's a way to have a single user with multiple UID but all I found was the opposite (multiple user with the same UID).
I also looked about the group permissions, but the GIDs of the files in the backups already exist on the local machine and I don't know if it's wise to add the user 500 to random groups.
Do you have any idea about that ?