v.24.9New Feature

Allow Multiple Authentication Methods Per User

Allow a user to have multiple authentication methods instead of only one. Allow authentication methods to be reset to most recently added method. If you want to run instances on 24.8 and one on 24.9 for some time, it's better to set max_authentication_methods_per_user = 1 for that period to avoid potential incompatibilities. #65277 (Arthur Passos).
Support for multiple authentication methods per user, allowing users to have more than one way to authenticate and reset to the most recently added method.

Why it matters

This feature enables more flexible and secure user authentication by allowing multiple authentication methods per user instead of just one. It helps manage smooth transitions between ClickHouse versions by avoiding incompatibilities during mixed-version deployments.

How to use it

Set the max_authentication_methods_per_user parameter to define how many authentication methods a user can have. To prevent issues when running mixed versions (e.g., 24.8 and 24.9), temporarily set this parameter to 1 during the transition period.