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-   -   nfs & uugidd (

Kropotkin 04-15-2006 03:39 PM

nfs & ugidd
Hi all,

I have a Fedora box with several NFS shares which I am mounting
locally under Ubuntu (Breezy). Since Fedora and Ubuntu don't have the
same uid/gids scheme, I have downloaded and installed uugid on the ubuntu system to map the ids. However, for some reason I am unable to open certain files on the remote system and it appears that while the user id is the same the group id for certain files is root. uugid appears not to remap the root gid and displays it as 1000; and hence I can't open them from the local machine.

I guess I don't understand completely how uugid works; I am expecting uids and gids to be mapped 1=1 between the two systems. Instead it seems I have to redo a lot of the permissions on the Fedora host to get things to work. The man page of uugid is pretty short, suggesting not much configuration is involved. Anyone here have any tips on how it works?

Emerson 04-16-2006 09:00 AM


Originally Posted by Kropotkin
Hi all,
I guess I don't understand completely how uugid works;

Sorry, but you do not understand how NFS and Linux works. There is NO reason why files owned by root should be accessible over NFS. Period. Use SSH for remote management.

Kropotkin 04-16-2006 10:38 AM

Right, but I am not dealing with system files, I am trying to open and write to files and directories in my home userspace, notably a large collections of jpegs. I have the same user name on both systems, but under Fedora my user ID number is 500 while under Ubuntu it is 1000 (system defaults). It is my understanding that in principle the uugid daemon is supposed to map the one to the other.

In practice, however, I am finding that I can access some directories and files but not others and I am trying to determine why. In a few places I saw that the group ID name was "root" which lead me to suppose that uugid does not map root on system a to system b.

Further, it appears I have to change the write permissions on certain directories to other +w to be able to see access them on the NFS client, even though the user and group names are the same.

At this point, I haven't figured out what the rules of the game, only that my id name is not being mapped 1 = 1 without restriction on the remote system.

Emerson 04-16-2006 12:58 PM

Sorry again, cannot help you any further. I use NFS alot, but I keep my UID's synced. useradd -u xxxx creates users with desired UID.

jerril 04-17-2006 01:28 PM


Originally Posted by Kropotkin
...The man page of uugid is pretty short, suggesting not much configuration is involved.

The correct program here, if anyone is looking for it is, "ugidd". I mention this because I wanted to correctly tag this thread.

Emerson, your suggestion seems to be an excellent solution for simple home networking with the least fuss. I am currently trying to run all of my machines using nfs for file sharing and samba (mostly to share my printer with my roomate). My plan was to use Ubuntu for everything, but I still want to experiment with other distros. I will use my server as a model for uid/gid designation.

I found a good discussion on the topic here:


Emerson 04-17-2006 01:49 PM

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