Not able to log on to XenMobile Server web console with administrator account.
The following errors are noticed in the logs:

2016-04-06T09:31:08.358+0800 | EDC68337B8501EEC | WARN | http-nio-14443-exec-9 | ZDMAuthenticationProvider | Could not find administrator 
2016-04-06T09:31:08.359+0800 | 85442C8CC2545C7F | WARN | http-nio-14443-exec-1 | DefaultAuthenticationImpl | Authentication failed for 'administrator': com.XXXXXX.core.XXXXXXXInstanceNotActiveException: XXXXXX instance is not active! 
SecurityException: com.XXXXXXXX.core.XXXXXXXNotActiveException: XXXXXX instance is not active! 

1. Reconfigure the cluster for XenMobile Server in the environment.
2. Restarted the XenMobile Server and it fixed the issue.

Problem Cause

1) Looks like the given username and password is first compared locally from the distributed map and in case it doesn’t find it there it goes to the database, but here it looks like we are running into an exception.

2) This doesn’t seem to be an issue with the Database, it rather looks like the issue is with the cluster config, since message of the authentication failure is the XXXX instance not being active.