A simple test to ensure the vasd processes running on a machine. On 4.x there should be five, a parent and five child processes.
This could be due to vasd being stopped or possible a segfault.
Resolution # 1
If possible simply restart vasd. Vasd can be started using normal systems commands. For example, on AIX this would work.
startsrc -s vasd
Resolution # 2
If vasd is crashing or segfaulting further investigation would be required. Please open a support case, include the core file and a back trace.
This article can help with collecting a backtrace.
A snapshot should also be included. Please run /opt/quest/libexec/vas/scripts/vas_snapshot.sh to collect a snapshot. This will create a file in /tmp that can be included with the case.