Серверу MySQL не удается запуститься: mysql.service перестал работать потому что процесс управления, из которого выходят с кодом ошибки

Работа выхода сервера MySQL, когда я устанавливал Drupal, последнюю версию. Затем я переустановил сервер MySQL, но без успеха. Этому не удается запуститься.

Вывод sudo service mysql start

Job for mysql.service failed because the control process exited with error code. 
See "systemctl status mysql.service" and "journalctl -xe" for details.

Вывод systemctl status mysql.service

? mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
   Active: activating (start-post) (Result: exit-code) since Sat 2017-05-13 23:40:38 UTC; 5s ago
  Process: 32760 ExecStart=/usr/sbin/mysqld (code=exited, status=1/FAILURE)
  Process: 32744 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
 Main PID: 32760 (code=exited, status=1/FAILURE); Control PID: 32763 (mysql-systemd-s)
Tasks: 2 (limit: 4915)
   Memory: 736.0K
   CPU: 58ms
   CGroup: /system.slice/mysql.service
       +-control
         +-  308 sleep 1
         +-32763 /bin/bash /usr/share/mysql/mysql-systemd-start post
May 13 23:40:38 ubuntu-512mb-tor1-01 systemd[1]: Starting MySQL Community Server...
May 13 23:40:38 ubuntu-512mb-tor1-01 mysql-systemd-start[32744]: my_print_defaults: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:40:38 ubuntu-512mb-tor1-01 mysql-systemd-start[32744]: my_print_defaults: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:40:38 ubuntu-512mb-tor1-01 mysqld[32760]: mysqld: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:40:38 ubuntu-512mb-tor1-01 mysqld[32760]: mysqld: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:40:38 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE

Вывод journalctl -xe

May 13 23:40:38 ubuntu-512mb-tor1-01 audit[32760]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=32760 comm="mysqld" requested_mask="
May 13 23:40:38 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718838.737:7854): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=3
May 13 23:40:38 ubuntu-512mb-tor1-01 audit[32760]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=32760 comm="mysqld" requested
May 13 23:40:38 ubuntu-512mb-tor1-01 audit[32760]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=32760 comm="mysqld" requested_mask="
May 13 23:40:38 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718838.741:7855): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/
May 13 23:40:38 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718838.741:7856): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=3
May 13 23:40:38 ubuntu-512mb-tor1-01 mysqld[32760]: mysqld: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:40:38 ubuntu-512mb-tor1-01 mysqld[32760]: mysqld: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:40:38 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE
May 13 23:41:08 ubuntu-512mb-tor1-01 systemd[1]: Failed to start MySQL Community Server.
-- Subject: Unit mysql.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has failed.
--
-- The result is failed.
May 13 23:41:08 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Unit entered failed state.
May 13 23:41:08 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Failed with result 'exit-code'.
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: Stopped MySQL Community Server.
-- Subject: Unit mysql.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has finished shutting down.
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: Starting MySQL Community Server...
-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has begun starting up.
May 13 23:41:09 ubuntu-512mb-tor1-01 mysql-systemd-start[362]: my_print_defaults: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:41:09 ubuntu-512mb-tor1-01 mysql-systemd-start[362]: my_print_defaults: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:41:09 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718869.245:7857): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378
May 13 23:41:09 ubuntu-512mb-tor1-01 audit[378]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378 comm="mysqld" requested_mask="r" den
May 13 23:41:09 ubuntu-512mb-tor1-01 audit[378]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=378 comm="mysqld" requested_mas
May 13 23:41:09 ubuntu-512mb-tor1-01 audit[378]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378 comm="mysqld" requested_mask="r" den
May 13 23:41:09 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718869.249:7858): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/
May 13 23:41:09 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718869.249:7859): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378
May 13 23:41:09 ubuntu-512mb-tor1-01 mysqld[378]: mysqld: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:41:09 ubuntu-512mb-tor1-01 mysqld[378]: mysqld: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE
lines 2142-2184/2184 (END)
May 13 23:40:38 ubuntu-512mb-tor1-01 audit[32760]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=32760 comm="mysqld" requested_mask="
May 13 23:40:38 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718838.737:7854): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=3
May 13 23:40:38 ubuntu-512mb-tor1-01 audit[32760]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=32760 comm="mysqld" requested
May 13 23:40:38 ubuntu-512mb-tor1-01 audit[32760]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=32760 comm="mysqld" requested_mask="
May 13 23:40:38 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718838.741:7855): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/
May 13 23:40:38 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718838.741:7856): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/32760/status" pid=3
May 13 23:40:38 ubuntu-512mb-tor1-01 mysqld[32760]: mysqld: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:40:38 ubuntu-512mb-tor1-01 mysqld[32760]: mysqld: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:40:38 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE
May 13 23:41:08 ubuntu-512mb-tor1-01 systemd[1]: Failed to start MySQL Community Server.
-- Subject: Unit mysql.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has failed.
--
-- The result is failed.
May 13 23:41:08 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Unit entered failed state.
May 13 23:41:08 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Failed with result 'exit-code'.
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: Stopped MySQL Community Server.
-- Subject: Unit mysql.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has finished shutting down.
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: Starting MySQL Community Server...
-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit mysql.service has begun starting up.
May 13 23:41:09 ubuntu-512mb-tor1-01 mysql-systemd-start[362]: my_print_defaults: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:41:09 ubuntu-512mb-tor1-01 mysql-systemd-start[362]: my_print_defaults: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:41:09 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718869.245:7857): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378
May 13 23:41:09 ubuntu-512mb-tor1-01 audit[378]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378 comm="mysqld" requested_mask="r" den
May 13 23:41:09 ubuntu-512mb-tor1-01 audit[378]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=378 comm="mysqld" requested_mas
May 13 23:41:09 ubuntu-512mb-tor1-01 audit[378]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378 comm="mysqld" requested_mask="r" den
May 13 23:41:09 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718869.249:7858): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/
May 13 23:41:09 ubuntu-512mb-tor1-01 kernel: audit: type=1400 audit(1494718869.249:7859): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/378/status" pid=378
May 13 23:41:09 ubuntu-512mb-tor1-01 mysqld[378]: mysqld: [ERROR] Found option without preceding group in config file /etc/mysql/my.cnf at line 24!
May 13 23:41:09 ubuntu-512mb-tor1-01 mysqld[378]: mysqld: [ERROR] Fatal error in defaults handling. Program aborted!
May 13 23:41:09 ubuntu-512mb-tor1-01 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE