portTest

#!/usr/bin/env bash

# 检查远程计算机是否正在侦听端口
# Reference: https://albertotb.com/bash-test-if-port-22-is-open/

# Usages: ./Test_port.sh $PORT -ip $HOST
# Examples: ./Test_port.sh 22
#           ./Test_port.sh 22 -ip localhost
#           ./Test_port.sh 22 -ip 192.168.9.1

# ssh -v 221.215.222.50 -p 10091
#       'Connection established' 则打开
#       ‘No route to host’ 则没打开

# echo > /dev/tcp/221.215.222.50/10091
#       没有任何输出则打开
#       有输出则没打开


host=localhost  # default

while [ "$1" != "" ]; do
    case $1 in
        -ip | --ip )            shift
                                host=$1
                                ;;
        * )                     port=$1
    esac
    shift
done

if [ -z $port ]; then
    echo "Usage: ./Test_port.sh <port>"
    echo "       ./Test_port.sh <port> -ip <host>"
    exit 1
fi

timeout=5

if nc -w $timeout -z $host $port > /dev/null 2>&1; then
   echo "Yes ---> HOST $host, PORT $port"
else
   echo "No ---> HOST $host, PORT $port"
fi