The value of errno translates to “Connection reset by peer”. Suspect are something strange happening in the network or hostname resolution of the server . Maybe check for errors or dropped packets?
protocol mis-match if you are using different versions of PBS Pro within your complex
You do not have to use PBS_LEAF_NAME here, please remove it.
PBS_SERVER=<hostname that is reverse address resolvable and same across all /etc/hosts of headnode and compute node >
This is old syntax, it is supported, better to switch to new syntax #PBS -l select=1:ncpus=1