Multiple app containers for a single Discourse site

Product Support Self-hosting
6

You’re right - I conflated two different topologies, and the thread title is the giveaway.

This topic is about “one server for 2 communities” (two independent sites).
My earlier “external Redis (single instance)” comment was describing a different pattern: “two app containers for one community” (HA / multi-web for a single site).

So to restate clearly:

A) Two independent Discourse sites on one server (what the OP is asking)

  • Treat them as two separate installs
  • They should have separate Postgres DBs and separate Redis instances (or at least isolation sufficient for MessageBus Pub/Sub, which is the gotcha you quoted)

B) One Discourse site with multiple web/app containers (what I was describing)

  • They must share the same Postgres DB and the same Redis for that site
    (sessions, rate limiting, MessageBus, etc.)

So: :white_check_mark: your Redis warning applies to A (two communities / two sites).
My “shared Redis” note only applies to B (one community scaled across multiple containers).

Thanks for the correction - I’ll keep the two cases explicitly separated in any follow-up runbooks/posts.