Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

ok, so I introduced a Mac laptop to my home network of Kubuntu hosts and Fedora servers. Currently I don't have NIS or LDAP setup (I got only 2 users) and I just manually setup the UID/GID on the hosts. I would like to run the following command on my Macbook:

dscl . -change /Users/me UniqueID 501 1000
dscl . -change /Users/me PrimaryGroupID 20 503
chown -R 1000:503 /Users/me
dscl . append /Groups/staff GroupMembership me

Before I go on to hose my new Mac, I would like to know if this is the right thing to do and, if so, what are the adverse consequences I may have.


share|improve this question
I don't know the answer, but I've always been wondered a bit by the procedure to preserve file ownership in Apple's How to change user short name or home directory name. Hence, without any reason whatsoever, I would also be a bit reluctant to mess with other user attributes... (Nice question!) – Arjan Apr 25 '10 at 17:06
@Arjan, very interesting info on the link you provided! Creating a new user would generate a new uid, so I feel a bit more comfortable changing that. Now Apple's default group is the "staff" with gid 20. I wonder if it is better to just add my 503 group instead of making it primary. Thanks for the insightful comment! – Peter Carrero Apr 25 '10 at 17:19
up vote 2 down vote accepted

well, throughout today I ended up doing exactly what I had outlined on the question. I've been using the mac the whole day today and so far, I've seen no adverse effect and I can finally access my NFS shares without problems. I guess continuous use will be the final test... If I do run into any issues I will update this answer.

share|improve this answer

today - months after the initial quest - i found an easier way of doing the same thing: using apple's server admin tools on your local mac. they can be found [here][1]. install and go to applications->server->workgroup manager.

in there you will see an option to change the uid of users (as well as a bunch of other options)

[1]: admin tools

share|improve this answer

I changed my uid to 1000 and the one adverse effect I have had is that my account is no longer displayed in the login window when it is set up to show icons for users. I know only see my wife's account and the "Other..." option where I have to click and then manually enter user name and password. Not a big hassle, but it is an extra couple clicks to get into my account.

share|improve this answer
Interesting point! I'm the only user of my mac, so this didn't happen to me. Thanks for the update. – Peter Carrero Jun 3 '10 at 11:46
Does anyone know the solution to this problem (or how to prevent it, in the first place)? – lindes Jan 21 '11 at 20:58

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.