Renumber users and groups

[Olivier Nicole]

Hello,

On my system legacy users come with UID starting from 200 upward, and
all users come with GID lower that 100.

I know it's not a good idea, but consider that some accounts are over 20
years old!

This is not too much a problem with FreeBSD as I can renumber the few
FreeBSD services that have a conflicting ID.

But now I want to share the user directories with Mac (10.6). On Mac,
any id lower than 512 should be reserved for the system.

I tried to renumber the conflicting services on Mac OS, but it messes up
the system.

So I should renumber my users; it's not very difficult to do, but I have
over 1TB of user files for 200 users.

Is there a clever/fast way to do that (other than find -exec chown)?

What pitfall should I avoid?

Best regards,

Olivier
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