NFS access failed for server: error 7 (RPC: 1832-010 Authentication error).

CAUSE:

 Port Mapper service of both “networker Remote exec”  and NFS tried to bind to port 111 while trying to start. Networker service was capturing it first. This caused port mapper service of NFS to fail.

 RESOLUTION:

 We stopped the Networker service and set it to Manual. After this we rebooted the server. This time the port mapper service of NFS could capture port 111 and hence it started successfully. After this NFS started functioning normally.

 This was followed by a restart of “Network Remote Backup Exec” service and set it to automatic. Though it didn’t get port 111 however it started using port no. 7938. It is designed to work this way in case the default port 111 is not available.  

 Going forward, how to stop the issue from reoccurring?

We need to make either of the below changes to stop the issue from reoccurring in future.

1)    Method 1: Make the NSREXECD (Networker Remote Exec) service dependent on NFS.

2)    Method 2: Prevent NSREXECD (Networker Remote Exec) service from trying to bind to port 111.

Method 1:

1)   Start Registry Editor. Click Start, click Run, type regedt32, and then click OK.

2)   Locate and then click the following registry key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\nsrexecd

3)   Add a REG_MULTI_SZ value that is named DependOnService, and then add portmap to the list.

4)   Click OK to close the dialog box, and then quit Registry Editor. The next time that you restart the server, Services for UNIX starts before the NetWorker Remote Exec service. The Services for UNIX port mapper can then bind to port 111.

Method 2:

In this method, we prevent NetWorker from trying to bind to port 111. We’ll edit the Nsrla.res file in the Program Files\Nsr\Res folder. The entry: emulate portmapper: Yes; needs to be changed to: emulate portmapper: No;

Neither of the above methods reduces the functionality of NetWorker. For lookups, NetWorker tries port 7938 first, and then fails over to 111.

+ Once the Active Directory replication stopped automatically you were trying to force the replication between two DCs.                                                                

RESULT: 

+ It was failing with the error “RPC server unavailable”.

CAUSE:

+ The DCs were not able to do the name resolution.

RESOLUTION:

+ First we updated the DNS.exe to the latest version and it didn’t resolve the issue.

+ Then we went ahead and removed the WINS checkbox from the DNS server properties. This didn’t resolve the issue.

+ After this we tried converting the zone to standard primary zone and this didn’t resolve the issue as well.

+ Then we deleted the dot zone from the DNS server. After this replication worked. Then we converted the zone back to AD integrated.