One or more NFSv4 mount points incorrectly show ownership by “nobody:nobody” instead of the correct ownership.
This is as-designed behavior and not an O/S-related issue. Instead, this is an NFSv3 versus NFSv4 behavioral difference.
In NFSv3, usernames and groupnames are mapped from the UserID (UID) and GroupID (GID) values in /etc/passwd. Remember, with NFSv3 UID and GID must be consistent across the entire client set.
If there is no local match for these UID or GID, the numeric value will be shown instead of a name.
In NFSv4, the concept is user@domainname; if there is no centralized user mapping, the user will be mapped to the properties defined in /etc/idmapd.conf; by default the name nobody will be used.
1. Ensure the proper domain is in the /etc/idmapd.conf file.
2. Restart the rpcidmapd service.
# service rpcidmapd restart
3. Remount the NFSv4 file system.
# /bin/mount -o remount /nfs/mount/point
Uniform UID and GID Assignment
It is a common misconception that the UID’s and GID’s can differ when using NFSv4. The sole purpose of ID mapping is to correlate the ID to a user name and vice-versa. ID mapping is not intended to replace proper management of network-wide UID and GID values.
If the above process does not remedy the issue, clear the idmapd cache:
# /sbin/nfsidmap -c