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I have an NFS4 share on an OpenIndiana server that I'm trying to properly access with an Ubuntu Linux machine.

The username that owns the files in the share on the server is "nick" its UID is 104 on the server. The group that owns the files on the server is "nick" and its GID is 100 on the server.

The same username/group exists on the Linux machine, but the UID is 112 and the GID is 112.

This is what I've done so far:

Created the entry in Linux's /etc/fstab to mount the share. This worked fine but when I did "ls -l" on the Linux machine, the user/group was set to nobody.

I edited /etc/default/nfs-common on the Linux machine and set "NEED_IDMAPD=yes". I also edited /etc/idmapd.conf on the Linux machine and set "Domain = lan", which is what it is set to on the OpenIndiana machine. I rebooted, and now:

When I go on the Linux machine and do "ls -l" in the share, the files show up as being owned by user "nick" and group "nick". Great! I thought I had it. But when I "su nick" and do "touch asdf", the file is created with the wrong username/group. When I view the newly created file on the OpenIndiana machine, it shows the username as 112 and the group as 112, as the file is being created with that UID/GID, but that doesn't map to any username/group on the OpenIndiana side.

So basically I have it halfway working. I can view files with the proper mapping, so idmapd is working at least somewhat, but the mapping is not being translated correctly the other way. What am I missing?

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up vote 0 down vote accepted

I found this link describing this exact problem. The writer came to the conclusion that this problem is unavoidable due basically to a design flaw in NFS4. I'm hoping that someone has some information about a fix.

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It's really incredible, but idmapd really doesn't do that! It took me 2 days to find that on the web (ie this one on gmane, or your link on dfusion) and another 2 days to believe that someone could have created such a surprisingly confusing mess.

no, talking about uid mapping, having ls -l print out mapped uids but letting it fail when accessing those files... jeee, tststs, headbang, no way!

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Tim, please modify your answer so that it is more usable. The Serverfault community doesn't generally care for link-only answers, which this one is close to. At first blush, the only technical information present in contained in the linked pages. If technical detail were added from the linked pages and attributed, this answer would more likely receive upvotes than its current downvotes. – Magellan Oct 3 '12 at 6:39

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