Scope/Description

• This article will cover resolving an issue when mounting NFS shares that are not honoring the permissions when mounted on a NFS client.

Prerequisites

• Storinator or Cluster with a configured storage pool
• SSH access to the server or cluster
• Configured and accessible NFS share(s)

Diagnosis

• On the NFS client we can see the issue with the ownership by running a ls -al on the mounted directory. There will also be error messages located in /var/log/messages.

• To diagnose this issue, on the client, run the following command:

cat /var/log/messages | grep nss_getpwnam

The output from this command should be something similar to:
nfsidmap[11441]: nss_getpwnam: name ‘user@exampledomain.com’ does not map into domain ‘localdomain’

This tells us there is an issue with the NFS share not mapping the proper domain credentials when mounted.

Resolution

• To resolve this issue, we need to modify the /etc/idmapd.conf file with the proper domain(FQDN). This change needs to be made on both the client and the server.

• We need to change the #Domain variable to:

Be sure to uncomment(remove the #) before Domain.

• From here, we need to restart the idmap service and clear the cache.

• Restart the service

systemctl restart nfs-idmapd.service

Clear the cache

nfsidmap -c

Remount the share

mount -o remount /nfs/mount/point

Verification

Running a ls -al command should now list the shared files with the proper ownership users and groups.