如何重写启动脚本

这篇文章给大家分享的是重写启动脚本的方法，相信大部分人都还没学会这个技能，为了让大家学会，给大家总结了以下内容，话不多说，一起往下看吧。

!/bin/bash

user=root
port=3306
CmdPath=/opt/mysql/bin
password=xxxxxxxxxx
base_dir=/opt/mysql
inst_dir=/data/3306
alive="00"
sMysqld=0
sMysqldSafe=0
fSock=0
fPID=0
check_alive()
{
echo "running check_alive..."      
if [ ps -ef | grep $port | grep -v grep | grep 'mysqld ' |awk '{print $2}' ];then
echo "Process mysqld is running!"
sMysqld=1
else
echo "Process mysqld is not running!"
sMysqld=0       
fi
    

 if [  `ps -ef | grep 3306 | grep -v grep | grep 'mysqld_safe' |awk '{print $2}'` ];then         echo "Process mysqld_safe is running!"        sMysqldSafe=1 else     echo "Process mysqld_safe is not running!"    sMysqldSafe=0     fi     if [ -e  ${inst_dir}/mysql.sock ];then        echo "socked file exists!"        fSock=1 else     echo "socked file not exists!"    fSock=0     fi     if [ -e  ${inst_dir}/mysql.pid ];then        echo "pid file exists!"        fPID=1 else     echo "pid file  not exists!"    fPID=0     fi     if [ $sMysqld -eq 1 ];then        if [ $fPID -eq 0 ];then            echo "PID is missing, tring to recreate..."            ps -ef | grep $port | grep -v grep | grep 'mysqld ' |awk '{print $2}' > ${inst_dir}/mysql.pid            if [ -e ${inst_dir}/mysql.pid ]; then                echo "pid file is created!"            else                echo "can not create PID file, please have a check!"            fi        fi        if [ $sMysqldSafe -eq 0 ];then            echo "Process mysqld_safe is missing, please have a check! May cause mysqld crash!"        fi        if [ $fSock -eq 1 ];then            echo "MySQL running fine!!!"            alive="11"        else            echo "socket file is missing, you may have to login without socket!"            alive="10"                  fi                               else        echo "process mysqld is missing, mysql is stopped!"        if [ $fSock -eq 1 ] | [ $fPID -eq 1 ];then            echo "mysql was stopped abnormality!"            echo "cleaning socket file and pid file"            alive="01"        else            alive="00"    fi
     fi

}
start_mysql()
{   
check_alive 
printf "MySQL is starting ... \n"
if [ $alive == "00" ]; then
${CmdPath}/mysqld_safe --defaults-file=${inst_dir}/my.cnf --user=${user} 2>&1 >/dev/null &
else
if [  $alive == "11" ]; then
echo "MySQL is runnig!"
else
if [ $alive == "01" ]; then
echo "MySQL was stopped but pid or sock file still exits!"
echo "Cleanning pid or sock files!"
if [ $fSock -eq 1 ];then
rm -f ${inst_dir}/mysql.sock
fi
if [ $fPID -eq 1 ];then
rm -f ${inst_dir}/mysql.pid
fi
echo "Tring to start MySQL again!!!"
${CmdPath}/mysqld_safe --defaults-file=${inst_dir}/my.cnf --user=${user} 2>&1 >/dev/null &
fi
fi
fi
}
stop_mysql()
{
check_alive
printf "MySQL is Stopping...\n" 
if [ $alive == "11" ]; then
${CmdPath}/mysqladmin -u root -p${password} -S ${inst_dir}/mysql.sock shutdown 2>&1 >/dev/null &       
else
if [ $alive == "10" ]; then
${CmdPath}/mysqladmin -u root -p${password} -h $HOSTNAME -P $port --protocol tcp shutdown 2>&1 >/dev/null &
else
echo "MySQL is not running, no need stop!" 
fi               
fi
}
restart_mysql()
{
stop_mysql
sleep 5
if [ $? == 0 ];then
start_mysql
else
echo "stop mysql failed!"
fi
}
case $1 in
start)
start_mysql
;;
stop)
stop_mysql       
;;
restart)
restart_mysql
;;
status)
status_mysql
;;
alive)
check_alive
;;
*)
printf "Please in put start|stop|restart|status as input"
;;
esac

}

以上就是重写启动脚本的方法，代码示例简单明了，如果在日常工作遇到此问题。通过这篇文章，希望你能有所收获，更多详情敬请关注行业资讯频道！