Odoo 19 PostgreSQL Replication Demo with ERPGAP

In this post, I show how to test PostgreSQL replication with Odoo 19, using a Docker Compose setup. The demo is based on:

• the YouTube video: “Odoo 19 w/ PostgreSQL Replication Demo”
• the GitHub repo: erpgap/Odoo-19-Replication-Demo

The goal is to have a primary database for writes and one or more replicas for reads, so Odoo can distribute load better, increase reliability, etc.

Overview

Here are the major pieces in this replication demo:

• A Docker Compose setup with two PostgreSQL nodes: the primary and a replica.
• Scripts in the repo to:
  • create a replication user
  • set up the connection between primary and replica
• Configuration of Odoo so that reads are directed to replica(s), writes go to the primary.
• A validation flow: create data, read data, monitor that reads are served from replica, while writes go to primary.

Setup Steps

Below are the concrete steps followed in the video / repo to get things working.

1. Prepare environment

docker compose down -v
docker compose up -d

• This shuts down existing containers and removes volumes to start from clean slate.
• Then brings up containers in detached mode.

You should see two PostgreSQL services:

• pg_primary (on port 5433)
• pg_replica (on port 5434)

2. Configure replication

• There is a script or SQL in the repo to create a replication user (called e.g. dd) in PostgreSQL.
• The replica is connected to the primary using this user.
• Odoo’s config file (odoo.conf) is set so that:

[options]
db_host = localhost
db_port = 5433               ; primary for writes
db_replica_host = localhost
db_replica_port = 5434       ; replica for reads

3. Run Odoo with the configuration

• Activate the virtual environment (if used) or otherwise ensure Odoo can be run with the configuration.
• Use the command:

odoo -c odoo.conf

• Make sure the replication user is created before starting, or else Odoo will throw an error about missing user.

4. Validate behavior

• Log in to Odoo (in the video it’s admin / admin).
• Install a module (like Sales).
• Create a product: e.g. Test 001. Saving it should perform a write → that should go to the primary.
• Do read operations (viewing records) multiple times to ensure they are served by the replica.

You can watch the logs on both pg_primary and pg_replica containers:

docker compose logs -f pg_primary
docker compose logs -f pg_replica

• Writes should appear in the primary logs
• Reads in the replica logs

Observations & Tips

• On local machines, things might seem slow, but this setup is mostly for demonstration / testing. ([YouTube][1])
• Odoo 19 has built-in capability (since ~18) to support read / replica routing; this approach relies on that.
• You can extend this by adding multiple read replicas to distribute read load further.

Conclusion

This replication demo is a great way to understand how Odoo + PostgreSQL can be set up for primary/replica, to enhance reading performance and resilience. The GitHub repo has all scripts and docker compose configs to get you started.

Video