Look in the file hpc.conf and change the default ranking of the SCI interface to give it the highest priority. That is, give it a lower number in the RANK column than any other interface listed in the file--for example, change its rank to 1.
If you don't know the hpc.conf file's location, do one of the following:
LSF - If your cluster is running LSF, open the LSF file /etc/lsf.conf. The LSF_CONFDIR entry in lsf.conf identifies the directory containing hpc.conf.
CRE - If your cluster is running the CRE, look in /opt/SUNWhpc/conf/hpc.conf.