netcat to check open port
nc -z -v 10.0.0.1 8080
check couple of hosts for port opening
PORT=8080 IP_LIST="10.0.0.1 10.0.0.2 10.0.0.3" TIMEOUT=3 # timeout in seconds for ip in $IP_LIST; do echo -n "$ip:$PORT " timeout $TIMEOUT nc -z -v $ip $PORT >/dev/null 2>/dev/null && echo '- OK' || echo '- NOT OK' done
