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/postgres.md.
Ivory

    PostgreSQL

    Plain PostgreSQL with streaming replication — a primary and its standbys, no HA tool in between. Not every setup needs automatic failover; this lets you watch and operate one without installing Patroni.

    Stage: STABLE

    At a glance

    • Cluster side — PostgreSQL itself, on the Keeper port, the same port as the database (5432)
    • Database side — PostgreSQL on the Database port
    • Keeper credentials — required: a PostgreSQL user; the cluster side logs into the database to read its state
    • Replication — one primary, any number of standbys
    • Lag — bytes of WAL a standby has not replayed yet; warns past 50 MiB

    How Ivory reads the cluster

    Each node is asked one connection's worth of questions per refresh:

    • Role — pg_is_in_recovery(): a node not in recovery is the primary, one in recovery is a standby.
    • From the primary — pg_stat_replication marks which standbys are synchronous. Standbys are matched by their application_name, so name each standby's replication connection after its node.
    • From a standby — pg_stat_wal_receiver names the server it streams from. That server is shown with an unknown role, because with cascading replication it may itself be a standby.
    • Lag — measured against the primary's reported WAL end; a standby with no WAL receiver running shows no lag at all rather than a misleading zero.
    • Also shown — the PostgreSQL version and connections in use out of max_connections.
    • Warnings — a standby that is not streaming, a replication slot past max_slot_wal_keep_size or one whose WAL is already lost, and replication details Ivory could not read.

    Reading the replication views in full needs a superuser or a member of pg_read_all_stats.

    Operations

    • Failover — promotes a standby with pg_promote(); refused on the primary
    • Reload the configuration with pg_reload_conf()
    • View the configuration (pg_settings)

    Switchover, restart, reinitialise and pause need an HA tool to coordinate them, so they are not offered — use PostgreSQL + Patroni for those.

    Query console

    The full PostgreSQL console — the same as for Patroni: SQL, schema browsing, dashboard, running queries with cancel and terminate, saved queries, and pgcompacttable.

    Deploying

    Both templates run the official postgres:18 image and create the user postgres. The first node is the primary; the other two clone it with pg_basebackup on first start and stream from it.

    • Postgres (Multi Host) — three nodes postgres1–postgres3, one per machine, all on port 5432. The standbys' commands name the primary's address literally (10.0.0.1:5432) — replace it with your primary's host before deploying.
    • Postgres (Single Host) — all three on one machine using host networking, on ports 5432–5434.

    See Deployment.