Shell Programming and Scripting

#!/bin/ksh

if [ $# -lt 3 ]; then
    print "usage: $0 <group> <userID> <serverfile>"
    exit 1
fi

NEWGROUP=$1
NEWUSER=$2
SERVERFILE=$3

for SERVER in `cat ${SERVERFILE}`
do
    if [ -n "`ping -c1 ${SERVER} 2>/dev/null | grep icmp_seq`" ]; then
        ISGROUP=`ssh ${SERVER} grep ${NEWGROUP} /etc/group`
        if [ ! -z "${ISGROUP}" ]; then
            ISUSER=`ssh ${SERVER} grep ${NEWUSER} /etc/passwd`
            if [ ! -z "${ISUSER}" ]; then
                ssh ${SERVER} usermod -g ${NEWGROUP} ${NEWUSER}
            else
                print "${NEWUSER} does not exist on ${SERVER}"
            fi
        else
            print "${NEWGROUP} does not exist on ${SERVER}"
        fi
    else
        print "${SERVER} is not reachable"
    fi
done