ClickHouse Incident Runbook

Overview

Step-by-step procedures for triaging and resolving ClickHouse incidents using built-in system tables and SQL commands. Start here: assess severity, run quick triage, walk the decision tree, then jump to the matching remediation procedure.

Prerequisites

• Network access to the ClickHouse HTTP interface (default port 8123) or a working clickhouse-client.
• A user with rights to read system.* tables and issue KILL QUERY / ALTER.
• Shell access to the host or container for P1 restarts (systemctl, docker, or kubectl).

Severity Levels