MySQL won't start 🐬 MySQL

Job for mysql.service failed because the control process exited with error code

The MySQL/MariaDB service failed to start — the real reason is in the MySQL error log.

Seen on: MySQL

Meaning

Common causes: disk full, corrupted InnoDB files after a crash, bad my.cnf options after an edit, wrong permissions on /var/lib/mysql, or port already in use.

Common causes

  • Invalid option in my.cnf
  • Disk full
  • Permissions on the data directory
  • InnoDB corruption / redo log mismatch after upgrade
  • Another process on port 3306

⚡ Quick fix

  1. Read the log: journalctl -u mysql and /var/log/mysql/error.log
  2. Revert recent config changes
  3. Free disk space
  4. Fix ownership: chown -R mysql:mysql /var/lib/mysql

Detailed fix by platform

Linux

  1. sudo journalctl -u mysql -n 80 --no-pager && sudo tail -n 80 /var/log/mysql/error.log

How to diagnose

  1. Log — First [ERROR] line?
  2. Change — Recent config edit or upgrade?

🧠 Still stuck? Analyze your error

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