Как выяснить почему не запускается MySQL?

Question

[Александр Петров]

Все было хорошо. НО! Вдруг я пытаюсь подключиться к БД, а она посылает меня куда подальше. В чем может быть дело?
У меня Centos7.

Я ни разу не сис-админ. Поэтому не понимаю, что мне пытаются сказать тут. Может надо еще больше инфы подкинуть, чтобы понять в чем дело?

[app@pervichka ~]$ sudo service mysqld start
Redirecting to /bin/systemctl start  mysqld.service
Job for mysqld.service failed because the control process exited with error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.

[app@pervichka ~]$ systemctl status mysqld.service
● mysqld.service - MySQL Server
   Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
   Active: failed (Result: start-limit) since Wed 2017-09-20 16:55:54 MSK; 10s ago
     Docs: man:mysqld(8)
           http://dev.mysql.com/doc/refman/en/using-systemd.html
  Process: 4918 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=1/FAILURE)
  Process: 4896 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)

Sep 20 16:55:54 pervichka systemd[1]: Failed to start MySQL Server.
Sep 20 16:55:54 pervichka systemd[1]: Unit mysqld.service entered failed state.
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service failed.
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service holdoff time over, scheduling restart.
Sep 20 16:55:54 pervichka systemd[1]: start request repeated too quickly for mysqld.service
Sep 20 16:55:54 pervichka systemd[1]: Failed to start MySQL Server.
Sep 20 16:55:54 pervichka systemd[1]: Unit mysqld.service entered failed state.
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service failed.

[app@pervichka ~]$ journalctl -xe
Sep 20 16:55:50 pervichka systemd[1]: mysqld.service: control process exited, code=exited status=1
Sep 20 16:55:50 pervichka systemd[1]: Failed to start MySQL Server.
-- Subject: Unit mysqld.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysqld.service has failed.
-- 
-- The result is failed.
Sep 20 16:55:50 pervichka systemd[1]: Unit mysqld.service entered failed state.
Sep 20 16:55:50 pervichka systemd[1]: mysqld.service failed.
Sep 20 16:55:50 pervichka systemd[1]: mysqld.service holdoff time over, scheduling restart.
Sep 20 16:55:50 pervichka systemd[1]: Starting MySQL Server...
-- Subject: Unit mysqld.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysqld.service has begun starting up.
Sep 20 16:55:52 pervichka mysqld[4879]: Initialization of mysqld failed: 0
Sep 20 16:55:52 pervichka systemd[1]: mysqld.service: control process exited, code=exited status=1
Sep 20 16:55:52 pervichka systemd[1]: Failed to start MySQL Server.
-- Subject: Unit mysqld.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysqld.service has failed.
-- 
-- The result is failed.
Sep 20 16:55:52 pervichka systemd[1]: Unit mysqld.service entered failed state.
Sep 20 16:55:52 pervichka systemd[1]: mysqld.service failed.
Sep 20 16:55:52 pervichka systemd[1]: mysqld.service holdoff time over, scheduling restart.
Sep 20 16:55:52 pervichka systemd[1]: Starting MySQL Server...
-- Subject: Unit mysqld.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysqld.service has begun starting up.
Sep 20 16:55:54 pervichka mysqld[4918]: Initialization of mysqld failed: 0
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service: control process exited, code=exited status=1
Sep 20 16:55:54 pervichka systemd[1]: Failed to start MySQL Server.
-- Subject: Unit mysqld.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysqld.service has failed.
-- 
-- The result is failed.
Sep 20 16:55:54 pervichka systemd[1]: Unit mysqld.service entered failed state.
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service failed.
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service holdoff time over, scheduling restart.
Sep 20 16:55:54 pervichka systemd[1]: start request repeated too quickly for mysqld.service
Sep 20 16:55:54 pervichka systemd[1]: Failed to start MySQL Server.
-- Subject: Unit mysqld.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysqld.service has failed.
-- 
-- The result is failed.
Sep 20 16:55:54 pervichka systemd[1]: Unit mysqld.service entered failed state.
Sep 20 16:55:54 pervichka systemd[1]: mysqld.service failed.
lines 3140-3200/3200 (END)

Comments

[Владимир Муковоз]

Сколько оперативки на сервере, случаем не 512Мб или меньше?

[Александр Петров]

Владимир Муковоз, 2гб

[Владимир Муковоз]

Александр Петров, покажи вывод команды
ls /var/lib/mysql

[Александр Петров]

[root@pervichka ~]# ls /var/lib/mysql
auto.cnf  ib_buffer_pool  ib_buffer_pool.incomplete  ibdata1  ib_logfile0  ib_logfile1  mysql  mysql_upgrade_info  performance_schema  pervichka  pervichka_test  sys

[Дмитрий Шапкин]

Покажите кусок лога mysql за 16:55

[Александр Петров]

Короче оказалось, что на сервере кончилось место и когда mysql пытался запуститься, он рухнул и сломался. Беда-беда((( Но! У меня есть бекапы, буду восстанавливать.

Answer 1

[Max Kostikov]

Посмотреть лог в рабочем каталоге MySQL. Обычно он имеет имя hostname.err