content_image/859214.jpg
password remains visible to ps . (SystemV Unix systems and perhaps others are subject to this problem.) 

If you are using MySQL Replication, be aware that, currently, a password used by a replica as part of a CHANGE REPLICATION SOURCE TO  statement (from MySQL 8.0.23) or CHANGE MASTER TO  statement (before MySQL 8.0.23) is effectively limited to 32 characters in length; if the password is longer, any excess characters are truncated. This is not due to any limit imposed by MySQL Server generally, but rather is an issue specific to MySQL Replication. 

## 6.2.15 Password Management 

MySQL supports these password-management capabilities: 

•Password expiration, to require passwords to be changed periodically. 

•Password reuse restrictions, to prevent old passwords from being chosen again. 

•Password verification, to require that password changes also specify the current password to be replaced. 

•Dual passwords, to enable clients to connect using either a primary or secondary password. 

•Password strength assessment, to require strong passwords. 

•Random password generation, as an alternative to requiring explicit administrator-specified literal passwords. 

•Password failure tracking, to enable temporary account locking after too many consecutive incorrect- password login failures. 

The following sections describe these capabilities, except password strength assessment, which is implemented using the validate_password  component and is described in Section 6.4.3, “The Password Validation Component” . 

•Internal Versus External Credentials Storage 

•Password Expiration Policy 

•Password Reuse Policy 

•Password Verification-Required Policy 

•Dual Password Support 

•Random Password Generation 

•Failed-Login Tracking and Temporary Account Locking 

<img src='content_image/859214.jpg'>

## Important 

MySQL implements password-management capabilities using tables in the mysql system database. If you upgrade MySQL from an earlier version, your system tables might not be up to date. In that case, the server writes messages similar to these to the error log during the startup process (the exact numbers may vary): 

[ERROR] Column count of mysql.user is wrong. Expected 49, found 47. The table is probably corrupted [Warning] ACL table mysql.password_history missing. Some operations may fail. 

