4091
MariaDBERRORCommonHIGH confidence
InnoDB data file access denied
Production Risk
High — Denied file access prevents InnoDB from operating on the affected tablespace.
Why it happens
- 1The data file is owned by a different user than the MySQL process.
- 2File permissions do not include read or write access for the MySQL user.
- 3A security policy (SELinux, AppArmor) is blocking file access.
Fix 1
Correct file ownership and permissions
Why this works
Run chown mysql:mysql <file> && chmod 660 <file> to set appropriate access.
Fix 2
Audit security policies
Why this works
Check SELinux audit logs or AppArmor logs for denials related to mysqld.
What not to do
✕
Sources
Official documentation ↗
MySQL 8.0 — 4091 ER_INNODB_DATAFILE_ACCESS_DENIED
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