Frequent ClickHouse Connection Failures Due to Incorrect Passwords

Symptom

The system displays a message indicating that the password is incorrect when it is correct. The clickhouse-server.log file contains the following information.

The auth.log file shows that the user is locked due to frequent failed authentication with incorrect passwords.

Cause Analysis

This may be caused by frequent failed login attempts on other services with incorrect passwords. If the number of failed login attempts exceeds the upper limit, the user is locked. The user will be unlocked only after the lockout period expires.

Solution

1. Check the ClickHouse logs and audit logs for the IP addresses that experience frequent access failures.
2. Identify the deployed services based on the IP address, and suspend the login attempts with incorrect passwords. After the lockout period expires, the user will be able to log in to ClickHouse.