常用的shell脚本

通用模板

#!/bin/bash

获取随机字符串或数字

# 8位随机字符串
echo $RANDOM |md5sum |cut -c 1-8
openssl rand -base64 4
cat /proc/sys/kernel/random/uuid |cut -c 1-8

# 8位随机数字
echo $RANDOM |cksum |cut -c 1-8
openssl rand -base64 4 |cksum |cut -c 1-8
date +%N |cut -c 1-8

检查软件包是否安装

# 检查sysstat是否已经安装
if rpm -q sysstat &>/dev/null; then
    echo "sysstat is already installed."
else
    echo "sysstat is not installed!"
fi

检查URL可用性

#!/bin/bash
function check_url(){
    HTTP_CODE=$(curl -o /dev/null --connect-timeout 3 -s -w "%{http_code}" $1)
    if [ $HTTP_CODE -ne 200 ]; then
        echo "Warning: $1 Access failure!"
    else
        echo $1": success!"
    fi
}

check_url "www.baidu.com"