Linux常用自启动

• mysql自启动：

• 将服务文件拷贝到init.d下，并重命名为mysqld
  # cp /usr/local/mysql/support-files/mysql.server /etc/init.d/mysqld
  赋予可执行权限
  # chmod +x /etc/init.d/mysqld
  添加服务
  # chkconfig --add mysqld
  显示服务列表
  # chkconfig --list

• nginx自启动：

• init.d目录下添加nginx文件
  # vi /etc/init.d/nginx

• #!/bin/bash
  # nginx Startup script for the Nginx HTTP Server
  # it is v.0.0.2 version.
  # chkconfig: - 85 15
  # description: Nginx is a high-performance web and proxy server.
  #              It has a lot of features, but it's not for everyone.
  # processname: nginx
  # pidfile: /var/run/nginx.pid
  # config: /usr/local/nginx/conf/nginx.conf
  nginxd=/home/nginx/sbin/nginx
  nginx_config=/home/nginx/conf/nginx.conf
  nginx_pid=/home/nginx/logs/nginx.pid
  RETVAL=0
  prog="nginx"
  # Source function library.
  . /etc/rc.d/init.d/functions
  # Source networking configuration.
  . /etc/sysconfig/network
  # Check that networking is up.
  [ ${NETWORKING} = "no" ] && exit 0
  [ -x $nginxd ] || exit 0
  # Start nginx daemons functions.
  start() {
  if [ -e $nginx_pid ];then
     echo "nginx already running...."
     exit 1
  fi
     echo -n $"Starting $prog: "
     daemon $nginxd -c ${nginx_config}
     RETVAL=$?
     echo
     [ $RETVAL = 0 ] && touch /var/lock/subsys/nginx
     return $RETVAL
  }
  # Stop nginx daemons functions.
  stop() {
          echo -n $"Stopping $prog: "
          killproc $nginxd
          RETVAL=$?
          echo
          [ $RETVAL = 0 ] && rm -f /var/lock/subsys/nginx /var/run/nginx.pid
  }
  # reload nginx service functions.
  reload() {
      echo -n $"Reloading $prog: "
      #kill -HUP `cat ${nginx_pid}`
      killproc $nginxd -HUP
      RETVAL=$?
      echo
  }
  # See how we were called.
  case "$1" in
  start)
          start
          ;;
  stop)
          stop
          ;;
  reload)
          reload
          ;;
  restart)
          stop
          start
          ;;
  status)
          status $prog
          RETVAL=$?
          ;;
  
  *)
          echo $"Usage: $prog {start|stop|restart|reload|status|help}"
          exit 1
  esac
  exit $RETVAL

• 标记部分，需要将路径改为自己机器的相应路径。接着设置文件访问权限。

• a+x参数表示 ========> all user can execute  所有用户可执行
  # chmod a+x /etc/init.d/nginx

• 最后将nginx加入到rc.local文件中，这样开机的时候nginx就默认启动了。

• 打开编辑rc.local文件
  # vi /etc/rc.local
  添加
  /etc/init.d/nginx start   
  保存并退出
  下次重启就会生效，实现nginx的自启动。

• 上面的设置不行，可以直接在rc.local中添加

• 编辑rc.local文件
  # vi /etc/rc.local
  添加nginx中启动文件安装路径到rc.local中
  # /usr/local/nginx/sbin/nginx
  设置执行权限
  # chmod 755 rc.local

• redis自启动：

• 将redis服务脚本redis_init_script移动到init.d目录下。ps: init.d目录---在系统启动的时候某些指定脚本将被执行 。
  # mv /home/redis-3.2.8/utils/redis_init_script   /etc/init.d
  将服务脚本改名为redis并修改配置信息
  # mv redis_init_script redis
  # vim redis
  复制一份redis.conf文件到etc目录下面
  # cp /home/redis/redis.conf  /etc/

  将服务脚本改名为redis并修改配置信息: (#内容也很重要)

• #!/bin/bash
  # chkconfig: 2345 90 10
  # description: Redis is a persistent key-value database

  REDISPORT=6379
  EXEC=/home/redis/bin/redis-server
  CLIEXEC=/home/redis/bin/redis-cli

  PIDFILE=/var/run/redis.pid
  CONF="/etc/redis.conf"

  case "$1" in
  start)
  if [ -f $PIDFILE ]
  then
  echo "$PIDFILE exists, process is already running or crashed"
  else
  echo "Starting Redis server..."
  $EXEC $CONF
  fi
  ;;
  stop)
  if [ ! -f $PIDFILE ]
  then
  echo "$PIDFILE does not exist, process is not running"
  else
  PID=$(cat $PIDFILE)
  echo "Stopping ..."
  $CLIEXEC -p $REDISPORT shutdown
  while [ -x /proc/${PID} ]
  do
  echo "Waiting for Redis to shutdown ..."
  sleep 1
  done
  echo "Redis stopped"
  fi
  ;;
  restart)
  "$0" stop
  sleep 3
  "$0" start
  ;;
  *)
  echo "Please use start or stop as first argument"
  ;;
  esac

• 增加文件执行权限
  # chmod +x /etc/init.d/redis
  加入服务,开机自启
  # chkconfig --add redis
  查看开机自启动项
  # chkconfig --list
  设置开机自启（关闭是off）
  # chkconfig redis on
  启动:
  # service redis start 
  # ps -ef|grep redis
  停止:
  # service redis stop

• jar包项目自启动：

• 在/etc/systemd/system目录下面新建一个启动文件 ，名称以service结尾，我这里的服务名称为config.service。操作如下：
  # vi /etc/systemd/system/config.service

  [Unit]
  Description=config service
  After=syslog.target
   
  [Service]
  Type=simple
  ExecStart=/home/java/bin/java -jar   -XX:MetaspaceSize=128m  -XX:MaxMetaspaceSize=128m -Xms1024m -Xmx1024m -Xmn256m -Xss256k -XX:SurvivorRatio=8 -XX:+UseConcMarkSweepGC -XX:+PrintGCDetails  /mnt/admin-1.0.jar
   
   
  [Install]
  WantedBy=multi-user.target

  当设置完成后就可以通过systemctl命令进行启动了。
  如设置为开机启动命令：
  # systemctl enable config.service
  启动服务命令
  # systemctl start config.service
  停止服务命令
  # systemctl stop config.service
  重新启动命令
  # systemctl restart config.service
  查看启动日志
  # journalctl -u config.service
  实时查看日志
  # journalctl -u config.service -f 
  查看日期日志
  #journalctl  -u config.service  --since  2020-07-08

• 来源：
  https://blog.csdn.net/tianlong1569/article/details/100539200?utm_medium=distribute.pc_relevant.none-task-blog-baidujs-1
  https://www.jianshu.com/p/276d59cbc529
  https://blog.csdn.net/qq_42810276/article/details/81296012