2189936 - Errors 968, 971 and 4001 can be raised by client on failover when using a single instance logical cluster, single instance database in SAP ASE CE.

• A client process connected to the base instance can raise Errors 968, 4001 in situations when the base instance is shutdown with nowait or otherwise fails over:

1> select @@instanceid, @@instancename, @@spid, suser_name(), db_id(), db_name()
2> go
Msg 968, Level 16, State 1:
Server 'testcluster':
Database 'database 'pubs2' (6)' is not upgraded and hence is not available for access. Please retry your query after database has been upgraded.
Msg 4001, Level 11, State 1:
Server 'testcluster':
Cannot open default database 'pubs2'.
1> 2>

 --- ------------------------------------------------------------ -----------
         ------------------------------------------------------------ ------
         ------------------------------------------------------------
   2 c2                                                                    54
         testlogin1                                                        1
         master

(1 row affected)

• This may also manifest as Errors 968, 4001 and 971:

Msg 968, Level 16, State 1: Server 'testcluster':
Database 'database '' (6)' is not upgraded and hence is not available for access. Please retry your query after database has been upgraded.
Msg 4001, Level 11, State 1: Server 'testcluster': Cannot open default database 'pubs2'.
Msg 971, Level 14, State 2:
Server 'testcluster', Line 1: Database 'pubs2' is currently unavailable. It is undergoing recovery of a critical database operation due to failure of a cluster instance. Wait and retry later.

• These errors occur when the client executes any SQL command immediately after the instance has been shutdown and before ASE has completed the failover and begins recovery of the default database. 
• A subsequent command by this same client immediately after the base instance has shutdown shows the database context has switched from the expected default database to master. This creates problems for the client  application that expects to reference objects locally in the default database. 
• This problem occurs when ASE CE is configured with a single instance logical cluster and single instance database.  

SAP Adaptive Server Enterprise Cluster Edition (ASE CE) 15.7 SP130 and higher

KBA , BC-SYB-ASE-CE , ASE Cluster Edition (Standalone) , Problem