Shell Programming and Scripting

#!/bin/bash -x

for i in `cat $1`
do
        _HOSTNAME=`echo $i |cut -d"." -f1`
        /usr/bin/ssh $i "
                echo $_HOSTNAME;
                for i in `/sbin/ifconfig -a | grep 172\.39 | awk '{print $2}'`
                do
                        if [[ -n `nslookup $i | grep $_HOSTNAME | awk '{print $2}'` ]]
                        then echo "backup interface OK"
                        else echo "backup interface NOT OK"
                        fi
                done
        " >> $1.out 2>/dev/null
done