MySQL Daemon failed to start on CentOS 6 after automatic update MySQL suddenly stopped working this night, after an automatic update of MySQL.

[root@lincl1161 xxxx]# service mysqld restart
mysqld stopped:                                            [  OK  ]
MySQL Daemon failed to start.
mysqld started:                                            [FAILED]                            


Here is my mysql.log file:

[root@lincl1161 xxxx]# tail /var/log/mysqld.log
170314  3:41:06 [Note] /usr/libexec/mysqld: Normal shutdown
170314  3:41:06 [Note] Event Scheduler: Killing the scheduler thread, thread id 1
170314  3:41:06 [Note] Event Scheduler: Waiting for the scheduler thread to reply
170314  3:41:06 [Note] Event Scheduler: Stopped
170314  3:41:06 [Note] Event Scheduler: Purging the queue. 2 events
170314  3:41:08 [Warning] /usr/libexec/mysqld: Forcing close of thread 3233579  user: 'admin'
170314  3:41:08 [Warning] /usr/libexec/mysqld: Forcing close of thread 3233578  user: 'admin'
170314  3:41:08 [Warning] /usr/libexec/mysqld: Forcing close of thread 3233575  user: 'admin'
170314  3:41:08 [Warning] /usr/libexec/mysqld: Forcing close of thread 3233574  user: 'admin'
170314  3:41:09  InnoDB: Starting shutdown...
170314  3:41:09  InnoDB: Waiting for 48 pages to be flushed
170314  3:41:10  InnoDB: Shutdown completed; log sequence number 53460683633
170314  3:41:10 [Note] /usr/libexec/mysqld: Shutdown complete
170314 03:41:10 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended


And the YUM log (the server uses Plesk):

[root@lincl1161 xxxx]# tail /var/log/yum.log
Jan 15 04:30:07 Updated: httpd-tools-2.2.15-56.el6.centos.3.x86_64
Jan 15 04:30:08 Updated: httpd-2.2.15-56.el6.centos.3.x86_64
Jan 15 04:30:08 Updated: 1:mod_ssl-2.2.15-56.el6.centos.3.x86_64
Jan 31 03:47:55 Updated: policycoreutils-2.0.83-30.1.el6_8.x86_64
Jan 31 03:48:07 Updated: selinux-policy-3.7.19-292.el6_8.2.noarch
Jan 31 03:48:45 Updated: selinux-policy-targeted-3.7.19-292.el6_8.2.noarch
Jan 31 03:48:49 Updated: psa-phpmyadmin-4.6.6-cos6.build1205170125.17.noarch
Jan 31 03:49:52 Updated: psa-selinux-12.5.30-cos6.build1205170125.17.noarch
Mar 14 03:40:51 Updated: mysql-libs-5.5.54-36.x86_64
Mar 14 03:40:54 Updated: mysql-5.5.54-36.x86_64
Mar 14 03:41:06 Updated: mysql-server-5.5.54-36.x86_64


No manual changes in server nor Plesk configurations have been made since months. Any help will be appreciated.
That issue is related to a broken update by Plesk.

Please read the article https://support.plesk.com/hc/en-us/articles/115001906725 .

You can fix it by running this command:

install -m 0700 -o mysql -g mysql -d /var/lib/mysql-files


and start mysql:

service mysqld start