來自公眾號：馬哥Linux運(yùn)維
作者：馬哥企業(yè)教練團(tuán)隊(duì)

生產(chǎn)環(huán)境下的Shell腳本還是挺多的，這里介紹幾個企業(yè)常見的Shell腳本。

1、MySQL數(shù)據(jù)庫備份腳本,下面的腳本是Mysql全量備份+異地備份

一般Mysql數(shù)據(jù)庫備份會采用在MYSQL從庫上執(zhí)行全量備份+增量備份方式。在從庫備份避免Mysql主庫備份的時候鎖表造成業(yè)務(wù)影響。

shell> vim db_backup.sh

#!/bin/bash  
# description:  MySQL buckup shell script  
# author:       magedu.com
# 192.168.10.10 為專門的備份服務(wù)器，需要做一下服務(wù)器之間免密碼登錄

#備份的數(shù)據(jù)庫名
DATABASES=(
            "magedu01"
            "magedu02"                    
)
USER="root"
PASSWORD="dbpwd123"

MAIL="magedu@gmail.com" 
BACKUP_DIR=/data/backup
LOGFILE=/data/backup/data_backup.log 
DATE=`date +%Y%m%d_%H%M`

cd $BACKUP_DIR
#開始備份之前，將備份信息頭寫入日記文件   
echo "--------------------" >> $LOGFILE   
echo "BACKUP DATE:" $(date +"%y-%m-%d %H:%M:%S") >> $LOGFILE   
echo "-------------------" >> $LOGFILE

for DATABASE in ${DATABASES};do
  /usr/local/mysql/bin/mysqldump -u$USER -p$PASSWORD --events  -R --opt  $DATABASE |gzip >${BACKUP_DIR}\/${DATABASE}_${DATE}.sql.gz
  if [ $? == 0 ];then
    echo "$DATE--$DATABASE is backup succeed" >> $LOGFILE
  else
    echo "Database Backup Fail!" >> $LOGFILE   
done
#判斷數(shù)據(jù)庫備份是否全部成功，全部成功就同步到異地備份f服務(wù)器
if [ $? == 0 ];then
  /usr/bin/rsync -zrtopg   --delete  /data/backup/* root@192.168.10.10:/data/backup/  >/dev/null 2>&1
else
  echo "Database Backup Fail!" >> $LOGFILE   
  #備份失敗后向管理者發(fā)送郵件提醒
  mail -s "database Daily Backup Fail!" $MAIL   
fi


#刪除30天以上的備份文件  
find $BACKUP_DIR  -type f -mtime +30 -name "*.gz" -exec rm -f {} \;

2、Nginx負(fù)載均衡服務(wù)器上監(jiān)控Nginx進(jìn)程的腳本

企業(yè)負(fù)載均衡層如果用到Nginx+Keepalived架構(gòu)，而Keepalived無法進(jìn)行Nginx服務(wù)的實(shí)時切換，所以這里用了一個監(jiān)控腳本check_nginx_pid.sh，每隔5秒就監(jiān)控一次Nginx的運(yùn)行狀態(tài)，如果發(fā)現(xiàn)有問題就關(guān)閉本機(jī)的Keepalived程序，讓VIP切換到從Nginx負(fù)載均衡器上。

shell> vim check_nginx_pid.sh

#!/bin/bash
while :
do
nginxpid='ps -C nginx --no-header | wc -l'
if ［$nginxpid -eq 0 ］;then
　　ulimit -SHn 65535
　　/usr/local/nginx/sbin/nginx
sleep 5
　nginxpid='ps -C nginx --no-header | wc -l'
　if ［$nginxpid -eq 0 ］;then
　/etc/init.d/keepalived stop
　fi
fi
sleep 5
done

3、MySQL主從監(jiān)控郵件報(bào)警腳本

此腳本應(yīng)該能適應(yīng)各種各樣不同的內(nèi)外網(wǎng)環(huán)境。
讓腳本也順便監(jiān)控下MySQL是否正常運(yùn)行。
Slave機(jī)器的IO和SQL狀態(tài)都必須為YES，缺一不可，這里用到了多重條件判斷-a。

shell> check_mysql_slave.sh
#!/bin/bash
#check MySQL_Slave Status

MYSQLPORT='netstat -na|grep "LISTEN"|grep "3306"|awk -F［:" "］+ '{print $4}''
MYSQLIP='ifconfig eth0|grep "inet addr" | awk -F［:" "］+ '{print $4}''
STATUS=$(/usr/local/mysql/bin/mysql -u dbuser -dbpwd123 -S /tmp/mysql.sock -e "show slave status＼G" | grep -i "running")
IO_env='echo $STATUS | grep IO | awk ' {print $2}''
SQL_env='echo $STATUS | grep SQL | awk '{print $2}''

if ［ "$MYSQLPORT" == "3306" ］
then
　echo "mysql is running"
else
　mail -s "warn!server: $MYSQLIP mysql is down" magedu@gmail.com
fi


if ［ "$IO_env" = "Yes" -a "$SQL_env" = "Yes" ］
then
　echo "Slave is running!"
else
　echo "####### $date #########">> /data/log/check_mysql_slave.log
　echo "Slave is not running!" >> /data/log/check_mysql_slave.log
　mail -s "warn! $MySQLIP_replicate_error" magedu@gmail.com << /data/log/check_mysql_slave.log
fi

# 建議每10分鐘運(yùn)行一次：
shell> crontab -e
*/10 * * * * root /bin/sh /root/check_mysql_slave.sh

4、系統(tǒng)初始化腳本

此腳本用于新裝Linux的相關(guān)配置工作，比如更換默認(rèn)yum源，優(yōu)化系統(tǒng)內(nèi)核、停掉一些沒必要啟動的系統(tǒng)服務(wù)等。此腳本尤其適合大批新安裝的CentOS系列的服務(wù)器。適用于Centos7

shell>vim cenots_7_system_init.sh
#!/bin/bash
# Filename:    centos7-init.sh
# Author:     magedu@gmail.com
#判斷是否為root用戶
if [ `whoami` != "root" ];then
echo " only root can run it"
exit 1
fi
#執(zhí)行前提示
echo -e "\033[31m 這是centos7系統(tǒng)初始化腳本，將更新系統(tǒng)內(nèi)核至最新版本，請慎重運(yùn)行！\033[0m" 
read -s -n1 -p "Press any key to continue or ctrl+C to cancel"
echo "Your inputs: $REPLY"
#1.定義配置yum源的函數(shù)
yum_config(){
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
yum clean all && yum makecache
}
#2.定義配置NTP的函數(shù)
ntp_config(){
yum –y install chrony
systemctl start chronyd && systemctl enable chronyd
timedatectl set-timezone Asia/Shanghai && timedatectl set-ntp yes
}
#3.定義關(guān)閉防火墻的函數(shù)
close_firewalld(){
systemctl stop firewalld.service &> /dev/null 
systemctl disable firewalld.service &> /dev/null
}
#4.定義關(guān)閉selinux的函數(shù)
close_selinux(){
setenforce 0
sed -i 's/enforcing/disabled/g' /etc/selinux/config
}
#5.定義安裝常用工具的函數(shù)
yum_tools(){
yum install –y vim wget curl curl-devel bash-completion lsof iotop iostat unzip bzip2 bzip2-devel
yum install –y gcc gcc-c++ make cmake autoconf openssl-devel openssl-perl net-tools
source /usr/share/bash-completion/bash_completion
}
#6.定義升級最新內(nèi)核的函數(shù)
update_kernel (){
rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
yum --enablerepo=elrepo-kernel install -y kernel-ml
grub2-set-default 0
grub2-mkconfig -o /boot/grub2/grub.cfg
}
#執(zhí)行腳本
main(){
    yum_config;
    ntp_config;
    close_firewalld;
    close_selinux;
    yum_tools;
    update_kernel;
}
main