RAC: sporadic problems with SCAN listener services

Hello,

 

since November 2011 we have experienced problems in different Oracle RAC environments concerning the SCAN listener services which lead to a system crash which are still unresolved.

The customers use Oracle version 11.2.0.2 Bundle Patch 14 or higher. One customer uses version 11.2.0.3.

Problem:

In an intervall of four weeks we have problems with the SCAN listener services. On both nodes we have sometimes a "check timed out" problem and the node of the RAC isn't reachable. Also a "crsctl stop cluster" fails during the stop and fail-over of the scan listener services. We also can't find a reasons for the problem. No changes on the network, shared storage, Windows update services .