验证某台主机是否在线

通过ping验证某台主机是否在线；

• ping命令

NAME：send ICMP ECHO-REQUEST to network hosts

OPTIONS：

-c count：Stop after sending count ECHO_REQUEST packets.

-i interval：Wait interval seconds between sending each packets.The default is to wait for one second between each packets normally.

-v：verbose output.

• 参数说明

$0：对应当前shell脚本的名称

$#：参数数量，一共有多少个参数

$*：所有位置的参数值

$1、$2.....：分别对应着第N个位置的参数值

$?：上一次命令的执行返回值，命令正确执行返回0，命令执行出错返回非0

• shell脚本

#! /bin/bash
# Detect whether the host is alive

IP=39.105.190.238
ping -c 4 -i 1 $IP >> /dev/null
[ $? -ne 0 ] && echo "host $IP does not exist" || echo "host $IP exists"

IP=2.2.2.2
ping -c 4 -i 1 $IP >> /dev/null
if [ $? -eq 0 ]
then
        echo "host $IP exists"
else
        echo "host $IP does not exists"
fi

• python脚本