Oracle Cluster Verification Utility (cluvfy) tracing.

If you get errors from Cluster Verification Utility (cluvfy) then you might need to get trace log out of it.
For example if you are creating Service Request about cluvfy into My Oracle Support you might add trace log into SR.

How to get trace log from cluvfy (run these as oracle user) :

1. Create directory for log:
mkdir /tmp/cvutrace

2. Set ENV variables:
export CV_TRACELOC=/tmp/cvutrace
export SRVM_TRACE=true
export SRVM_TRACE_LEVEL=1

3. Run wanted cluvfy check:
runcluvfy.sh .....

For example:
/data/install/grid/runcluvfy.sh stage -pre crsinst -n node1,node2 -r 11gR2 -verbose

After the cluvfy run is completed you'll have its trace log in the directory you created.
Copy it and add into the SR.

More info from MOS (My Oracle Support):
MOS ID 986822.1