It would do yourself much good if you decide to synchronize uids/gids in your whole organization, the overall maintenance effort would be much easier.
And it can be achieved in a relatively painless way:
- create or configure your central directory
- decide on uid/gid space you would like to use (make sure it does not overlap anything you're using now and do not remap uids that will be local to the hosts only - system and daemon accounts etc.)
- schedule maintenance break for every of your machines
- prepare a script to reset the ownership after remapping users; something like this worked once for me:
find /path/to/what/has/to/be/preserved -printf "chown -c %u:%g \"%h/%f\"\n" > preserve- switch to your new directory service
- remove or remap the non-system part of your /etc/passwd and /etc/group
- restore the file/directory ownership by running the generated script (sh preserve will do)
- rinse, repeat, profit!
Notes:
- the generated script is not efficient at all, as it's changing back ownership one file by one; but it should be a good demonstration of the general idea.
- if you have any suid/sgid binaries and directories there, record them in the script as well, for example by changing the printf clause to "chown -c %u:%g "%h/%f"\nchmod -c %m "%h/%f"\n"