For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt, and this page is available as Markdown at /docs/databases/clickhouse.md.
Ivory

    ClickHouse

    A ClickHouse cluster with replicated tables, coordinated through ZooKeeper or ClickHouse Keeper. Every node accepts writes, so there is no leader — Ivory shows every member as a replica and watches replication health.

    Stage: BETA

    At a glance

    • Cluster side — ClickHouse's native protocol, on the Keeper port, the same port as the database (9000)
    • Keeper credentials — password required
    • Replication — every node writes; replicas converge through the coordination store
    • Lag — seconds of replication delay; warns past 30 s

    How Ivory reads the cluster

    • Members — Ivory reads system.clusters for the cluster named exactly like the cluster in Ivory, so name your Ivory cluster after the <remote_servers> entry. A node that declares no such cluster gets a warning listing the clusters it does declare.
    • Roles — every member is a replica: ClickHouse has no leader.
    • Lag — the largest absolute_delay across the node's replicated tables.
    • Warnings — replicated tables gone read-only (usually a lost session with the coordination store), replicas without an active coordination session, stuck tasks in the replication queue with the error that blocks them, and delay past ClickHouse's own max_replica_delay_for_distributed_queries.

    Operations

    • Reload the configuration (SYSTEM RELOAD CONFIG)
    • View the settings (system.settings)

    With no leader, there is nothing to switch over or fail over.

    Query console

    SQL, with browsing of databases and tables and a dashboard (databases, connections, sizes, uptime). Saved queries cover active queries, the replication queue, the coordination connection, detached parts, disks and more. Running queries cannot be cancelled from Ivory: ClickHouse identifies them by a string id, not a process id.

    Deploying

    Both templates run clickhouse/clickhouse-server:24, write the cluster into a config.d file before starting and create the database user named on the deploy screen (default unless you change the template). The macros {cluster} and {replica} are set to the Ivory cluster and node name. ClickHouse needs a ZooKeeper (or ClickHouse Keeper) — the deploy screen asks for its <node> entries once, for the whole cluster.

    • ClickHouse (Multi Host) — three nodes clickhouse1–clickhouse3, one per machine, on port 9000. The replica list names 10.0.0.1–10.0.0.3; replace the addresses before deploying.
    • ClickHouse (Single Host) — all three on one machine on ports 9000–9002. Its coordination store defaults to the ZooKeeper single-host template, so deploy that first on the same machine.

    See Deployment.

    Good to know

    • The Ivory cluster name is written into ClickHouse's XML config, so it must be a valid XML element name.
    • Under docker's bridge networking CREATE … ON CLUSTER can hang; create replicated tables on each node instead.