User name mapping not working through ADlookup

Recently we had an issue where User Name Mapping were not working through ADlookup. Initially it looks to be some issue with either the UID\GID not been set properly or some configuration issue. While we were troubleshooting on the issue, we confirm that the correct UID\GID has been populated in the AD. The netbios name for the domain has been populated properly. The NFS file versions was also updated.

One more thing came out during the troubleshooting. The environment at customer’s end was:

There was a parent DC, child DC and a member server for a child DC.

NFS server was configured on the member server and the User was there in the child DC. But in the ADlookup setting we were putting the ‘netbios’ name for the Parent domain instead of the child domain. We made the changes and things started working.

We also tested and concluded the below behaviour:

1. In case the NFS server is a member server for a child domain. And the user is also in the child domain; in that case you need to mention the NetBIOS name of the child domain and not the parent domain.

2. In case the NFS server is a member server for a child domain. And the user is on the parent domain; in that case you need to mention the NetBIOS name of the Parent domain and not the child domain.