Shell常用脚本

[root@nginx ~]# sh /etc/scripts/process.sh

#!/bin/bash

FILENAME=`basename $0 .sh`                  #获取脚本文件名称，不包含.sh后缀
FILEPATH=`dirname $0`
echo "PID of this script: $$"               #($$)查看当前脚本的进程ID
echo "PPID of this script: $PPID"           #($PPID)查看当前脚本父进程的进程ID
echo "UID of this script: $UID"             #($UID)查看用户的UID
echo $$ >$FILEPATH/$FILENAME.pid            # 保存脚本进程号到文件
echo "当前是第$LINENO行"                      #$LINENO获取当前行号
echo "文件名不包含.sh: $FILENAME"             #脚本文件名
echo "文件路径: $FILEPATH"                   #脚本路径

[root@nginx ~]# sh /etc/scripts/datatime.sh

#!/bin/bash

# 查看所有时区名称(tzselect：选择时区)
# timedatectl list-timezones
# 获取UTC时间
date -u '+%Y-%m-%dT%H:%M:%SZ'
# 转换UTC时间格式为北京时间
date -d "2024-10-22T07:23:05Z" '+%Y-%m-%d %H:%M:%S'
# 获取秒级时间戳
timestamp=$(date +%s)
# 获取毫秒级时间戳
timestamp_ms=$(date +%s%3N)
# 毫秒和秒转换
# timestamp=$((timestamp_ms / 1000))
# 获取utc时间戳
timestamp=$(date -u +%s)
# 将时间戳转换为utc时间
date -u -d @"$timestamp" '+%Y-%m-%dT%H:%M:%SZ'
# 将时间戳转换为北京时间
beijing_time=$(TZ='Asia/Shanghai' date -d @"$timestamp" '+%Y-%m-%d %H:%M:%S')
echo $beijing_time

[root@web01 scripts]# cat ping.sh     #并发执行ping（快速执行加{ }&）

#!/bin/bash 
for n in {1..254};do
    {
    ping -c 1 10.0.0.$n &>/dev/null
    if [ $? -eq 0 ];then
        echo "10.0.0.$n" >>/tmp/cunhuo.log
    else
        echo "10.0.0.$n" >>/tmp/dead.log
    fi
}&
done
wait      #wait等待前面的后台任务全部完成才往下执行
echo "hello world"

[root@web01 scripts]# cat iptables.sh       #自动封IP

#!/bin/bash
. /etc/init.d/functions
if [ $UID -ne 0 ];then
    echo "Please use root run scription!!!!!"
    exit 10
fi
while true
do
    awk '{print $1}' /application/nginx/logs/access.log|sort -n -r|uniq -c >/tmp/ip.txt
    while read LINE
        do
            IP=${LINE#* }
            COUNT=${LINE%% *}
            ADD_IP=$(iptables -nL|egrep $IP|wc -l)
            IPTABLES(){
                if [ "$COUNT" -gt 5 -a $ADD_IP -eq 0 ];then
                    iptables -I INPUT -s $IP -j DROP
                    action "$IP is dropped!!!!!!"  /bin/true
                elif [ $COUNT -lt 5  ];then
                    iptables -D INPUT -s $IP -j DROP 2>/dev/null
                fi
            }
            IPTABLES 
        done </tmp/ip.txt
    sleep 60
done

[root@db02 3306]# cat fenku.sh    # Mysql分库备份

#!/bin/bash
port=3306
socket=/data/${port}/mysql.sock
CmdPath="/application/mysql/bin"
MysqlCmd="mysql -S $socket"
MysqlDump="mysqldump -S $socket"
DataPath=/data/backup
[ -d $DataPath ] || mkdir $DataPath -p
for dbname in `$CmdPath/$MysqlCmd -e "show databases;"|sed 1d|grep -v "_schema"`
do
   $CmdPath/$MysqlDump  -B --master-data=2 $dbname|gzip >$DataPath/${dbname}_$(date +%F).sql.gz
done

[root@web01 scripts]# cat md5sum.sh

#!/bin/sh
array=(
21029299
00205d1c
a3da1677
1f6d12dd
890684b
)
Path=/tmp/md5.txt
funGetMd5() {
    > $Path
    for ((Num=0;Num<=32767;Num++))
    do     
       {
       Stat=$(echo $Num|md5sum)
       echo "$Stat $Num" >> $Path
       }&     
    done
}
funFindMd5() {
    word=$(echo "${array[@]}"|sed -r 's# |\n#|#g')
    grep -E "$word" $Path
}
funcMain(){
    funGetMd5
    funFindMd5
}
funcMain

[root@web01 scripts]# cat arr3.sh 

#!/bin/sh
. /etc/init.d/functions
array=(
http://blog.oldboyedu.com
http://blog.etiantian.org
http://oldboy.blog.51cto.com
http://10.0.0.7
)
function wait(){
    echo -n "Start Curl_check"
    for n in {1..3}
    do
        echo -n " ."
        sleep 1
        if [ $i -eq 4 ];then
            echo -e "\t"
            action "Curl_check is start!!!!!!" /bin/true
        fi
    done
}
function check_url(){
    wget -o /dev/null --spider -T 10 --tries=1  $1 
    if [ $? -eq 0 ];then
        action "$1 is ok" /bin/true
    else
        action "$1 is no" /bin/false
    fi
}
function main(){
    wait
    for((i=0;i<${#array[*]};i++))
    do
        check_url ${array[i]}
        sleep 1
    done
}
main

[root@nginx ~]# cat func.sh $1

#!/bin/bash
. /etc/init.d/functions
function name() {
    if [ -z $1 ];then
        echo "Usg:sh $0 [ip/domain]"
        return 1
    else
    ping -c 3 $1 >/dev/null
        if [ $? -eq 0 ];then
            echo "up"
        else
            echo "down"
            return 2
        fi
    fi
}
result=$(name $1)   #取函数的运行结果，以及向函数里传参
echo $?             #取函数的return值
if [ "$result" == "down" ];then
    /sbin/ifdown eth1 >/dev/null
    action "eth1 is down" /bin/true
elif [ "$result" == "up" ];then
    /sbin/ifup eth1 >/dev/null
    action "eth1 is up" /bin/true
else
    echo $result
fi

[root@nginx ~]# cat menu.sh   #打印菜单脚本

#!/bin/sh
clear
echo -e "\n\n\t\t\tScripts admin menu"
echo -e "\n\t\t++++++++++++++++++++++++++++\n"
echo -e "\t\t1.  Install Apche"
echo -e "\t\t2.  Install PHP"
echo -e "\t\t3.  Install Mysql"
echo -e "\n\t\t++++++++++++++++++++++++++++"
echo -en "\n\t\t  Please enter Install option: " 
read -t 5 -n 1 NUM
case $NUM in 
    1) 
    echo -e "\n\nInstall Apple\n"
    ;;
    2) 
    echo -e "\n\nInstall PHP\n"
    ;;
    3)
    echo -e "\n\nInstall Mysql\n"
    ;;
        *)
        echo -e "\n\n\tUsge: Enter 1|2|3\n"
esac

[root@nginx ~]# cat captrue.sh   #自动抓包脚本

#!/bin/bash
n=1
while true;do
  tcpdumpid=`ps aux | grep tcpdump | awk '/^tcpdump/{print $2}'`
  curl 172.30.3.198:6011 &>/dev/null
  if [ $? -ne 0 ];then
    echo "$n `date +"%Y-%m-%d %T"` ---curl 172.30.3.198 false..." >>./status_error.log
    num=`ps aux | grep tcpdump| wc -l`
    if [ $num -eq 1 ];then
      tcpdump src host 172.30.4.152 and dst host 172.30.3.198 -w ./server_152.cap &
    fi
  else 
    kill $tcpdumpid >/dev/null 2>&1
    [ -f ./server_152.cap ] && mv ./server_152.cap ./server_$(date +%F-%T)_152.cap
    echo "$n `date +"%Y-%m-%d %T"` ---curl 172.30.3.198 ok..." >>./status.log
  fi
  ((n++))
  sleep 2
done

[root@localhost ~]# cat clearlog.sh    # 清理指定月份之前的日志

#!/bin/bash

month=$(date +%m)
if [ $month -gt 3 ];then
    let max_month=month-3
    if [ $max_month -lt 10 ];then
        num=0$max_month
    else
        num=$max_month
    fi
    for m in `seq -s ' ' -w 1 $num`; do
            if [ -d $m ];then
                rm -rf $m
                echo $(date +%F" "%T) 清理$m月日志目录  >>/var/log/clean.log
            fi
done
fi

[root@localhost ~]# cat test.sh   #打印99乘法表

#!/bin/bash

for i in `seq 9`
do
    for j in `seq $i`
        do
            [ $[i*j] -eq 6 ] || [ $[i*j] -eq 8 ] && [ $j -ne 1 ] && echo -n "$j*$i=$[i*j]   " || echo -n "$j*$i=$[i*j]  "
        done
    echo
done

Shell并发脚本

#!/bin/bash  

# 最大并发数
max_jobs=3
# 计数器
count=0

run_task() {
    sleep "$1"
    echo "Task with sleep $1 seconds completed."
}

for i in {1..10}; do
    # 启动任务并放入后台
    run_task $((RANDOM % 5 + 1)) &
    # 递增计数器
    ((count++))
    # 控制最大并发数
    if [ "$count" -ge "$max_jobs" ]; then
        # 等待任一后台进程完成，有些shell版本不支持-n选项
        wait -n
        # 递减计数器
        ((count--))
    fi
done
# 等待最后的后台进程完成
wait
echo "All tasks are completed."

Shell逐行读取文件

# 方法一，指定换行符读取：
#!/bin/bash
IFS="\n"
for LINE in `cat /etc/passwd`
do
    echo $LINE
done

# 方法二，使用管道符将前面命令的输出传递给read处理：
echo -e "line1 hello world\nline2 this test" | while read LINE;do echo "$LINE" && sleep 1;done
# 以空格为分隔符，read将读取的第一部分赋值给变量VAR1，第二部分赋值给变量VAR2，第三部分赋值给变量VAR3
# -r 选项表示原样读取，不解析反斜杠，保持输入中的特殊字符的原始形式，不进行转义处理
echo -e "line1 hello world\nline2 this test" | while read -r VAR1 VAR2 VAR3;do echo "$VAR1--$VAR2--$VAR3";done

# 方法三，用read读取文件重定向：
# while read LINE;do echo $LINE && sleep 1;done < /etc/passwd
#!/bin/bash
while read LINE
do
    echo $LINE && sleep 1
done < /etc/passwd

[root@localhost ~]# seq -s ' ' -w 1 05  #-s：指定分隔符，默认分割符为'\n'，-w 1 05：从1到5
01 02 03 04 05
[root@localhost ~]# date +%Y/%m/%d" "%H:%M:%S
2023/05/17 10:20:47
[root@localhost ~]# date +%F" "%T
2023-05-17 10:20:38
[root@localhost ~]# useradd -M -U -s /sbin/nologin user1  #添加用户和组，组名同用户名;-M,不创建用户家目录
[root@localhost ~]# echo '123456' | passwd --stdin user1  #设置用户密码

检查k8s pod状态并将结果推送到Prometheus pushGateway

#!/bin/bash
# 检查k8s pod状态并将结果推送到Prometheus pushGateway
# kubectl get pod | awk 'NR>1{if($3=="Running"){printf "{\"module\":\"%s\",\"status\":\"正常\"} ",$1}else{printf "{\"module\":\"%s\",\"status\":\"异常\"} ",$1}}'
jobName="K8S_Pod状态检查"
instanceName="XXXXXX"
pushGatewayAddress="http://x.x.x.x:30005/metrics/job/${jobName}/instance/${instanceName}"


checkres=$(kubectl get pod -o wide | awk 'NR>1{if($3=="Running" || $3=="Completed"){printf "check_node_pod{pod=\"%s\",status=\""$3"\",nodename=\""$7"\"} 1\n",$1}else{printf "check_node_pod{pod=\"%s\",status=\""$3"\",nodename=\""$7"\"} 0\n",$1}}')
cat <<EOF | curl --data-binary @- ${pushGatewayAddress} 
  # TYPE check_node_pod gauge
  # HELP check_node_pod 1->success 0->failure
  $checkres
EOF


checkres=$(kubectl get pod -o wide | awk 'NR>1{split($1,arr,"-");if(length(arr)<3){res=arr[1]}else{res=arr[1]"-"arr[2]};if($3=="Running" || $3=="Completed"){printf "check_node_pod{pod=\"%s\",status=\""$3"\",nodename=\""$7"\"} 1\n",res}else if(res!="chrony" && $3!="Running"){printf "check_node_pod{pod=\"%s\",status=\""$3"\",nodename=\""$7"\"} 0\n",res}}')
cat <<EOF | curl --data-binary @- ${pushGatewayAddress}
  # TYPE check_node_pod gauge
  # HELP check_node_pod 1->success 0->failure
  $checkres
EOF

read   -p     接提示语句
          -t 3   超时设置（单位为秒）
          -n 3  允许输入的最大字符串个数，大于3个直接退出
          -s     隐藏输入的字符串

while循环的特长是执行守护进程，以及实现我们希望循环不退出持续执行的应用，擅长用于频率小于1分钟循环处理,其他的while循环几乎都可以被for循环取代
if语句、for语句最常用，其次while（守护进程），case（服务启动脚本）
sleep默认单位秒(s)，usleep默认单位微秒(μs)

标准输入stdin，标准输出stdout和标准错误stderr，三个系统文件的文件描述符分别为0，1和2。所以2>&1的意思就是将标准错误也输出到标准输出当中

Ubuntu中编写脚本时报错 let: not found，原因为在Ubuntu中/bin/sh链接默认指向的是dash shell，dash是一个小巧的shell，而dash shell不支持++运算和let命令
解决办法:
     1、直接指明使用bash shell
     2、sudo dpkg-reconfigure dash 选择 "否", 表示用bash代替dash

参考链接：
       https://blog.51cto.com/cuimk/1347743       # iptables交互脚本
       https://segmentfault.com/a/1190000009745139      # shell分析日志文件
       https://github.com/sqshq/sampler        # Linux监控工具sampler