Starting MySQL.. ERROR! The server quit without updating PID file (/db/data/110.pid).

[root@110 db]# systemctl status mysql
● mysqld.service - LSB: start and stop MySQL
   Loaded: loaded (/etc/rc.d/init.d/mysqld; bad; vendor preset: disabled)
   Active: failed (Result: exit-code) since 五 2019-08-09 04:54:08 CST; 11s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 7851 ExecStop=/etc/rc.d/init.d/mysqld stop (code=exited, status=0/SUCCESS)
  Process: 8751 ExecStart=/etc/rc.d/init.d/mysqld start (code=exited, status=1/FAILURE)
   CGroup: /system.slice/mysqld.service
           ├─7092 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/db/data --pid-file=/db/data/110.pid
           └─7269 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/db/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/var/log/mysqld.log --pid-file=/db/data/110.pid --...

8月 09 04:54:06 110 systemd[1]: Starting LSB: start and stop MySQL...
8月 09 04:54:08 110 mysqld[8751]: Starting MySQL.. ERROR! The server quit without updating PID file (/db/data/110.pid).
8月 09 04:54:08 110 systemd[1]: mysqld.service: control process exited, code=exited status=1
8月 09 04:54:08 110 systemd[1]: Failed to start LSB: start and stop MySQL.
8月 09 04:54:08 110 systemd[1]: Unit mysqld.service entered failed state.
8月 09 04:54:08 110 systemd[1]: mysqld.service failed.

　遇到了以上无法启动的问题，查看了以下mysql的进程，发现进程还在

kill一下试试

[root@110 db]# ps -ef | grep mysql
root       7092      1  0 03:31 ?        00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/db/data --pid-file=/db/data/110.pid
mysql      7269   7092  0 03:31 ?        00:00:01 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/db/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/var/log/mysqld.log --pid-file=/db/data/110.pid --socket=/tmp/mysqld.sock
root       9131   7654  0 05:00 pts/0    00:00:00 grep --color=auto mysql

[root@110 db]# kill -9 7092
[root@110 db]# 
[root@110 db]# ps -ef | grep mysql
mysql      7269      1  0 03:31 ?        00:00:01 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/db/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/var/log/mysqld.log --pid-file=/db/data/110.pid --socket=/tmp/mysqld.sock
root       9133   7654  0 05:00 pts/0    00:00:00 grep --color=auto mysql

再次查看，发现还有，继续kill

[root@110 db]# kill -9 7269
[root@110 db]# ps -ef | grep mysql
root       9149   7654  0 05:01 pts/0    00:00:00 grep --color=auto mysql
[root@110 db]# 

没有了，启动mysql试一下

[root@110 db]# systemctl start mysql
[root@110 db]# mysql -u root -p 
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 2
Server version: 5.7.27 Source distribution

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