Troubles connecting to local postgres docker database

[Emanuel_Maricic]

Hey, I have a problem connecting my local database to n8n, I have a docker running on port 5432.

When I set host to localhost or 127.1.0.0 it throws the error connection refused and when I try to connect through bridge IP address it is just loading and not doing anything until I manually close it. Thank you in advance

docker config:

version: "3.8"

services:
  postgres:
    image: postgres
    container_name: n8n
    ports:
      - "5432:5432"
    environment:
      - POSTGRES_DB=postgres
      - POSTGRES_USER=postgres
      - POSTGRES_PASSWORD=postgres
    networks:
      - n8n-network

networks:
  n8n-network:
    driver: bridge

[Erick_Torres]

The error is due to a common confusion when using Docker:
When n8n is in a separate container, localhost refers to the n8n container, not the host.

Therefore:

• localhost or 127.0.0.1 will not work from within a separate n8n container.
• Port 5432 is exposed to the host, but not necessarily to other containers via localhost.

You should use the service name as the host
Host: postgres
instead of localhost or IP.

Why does it work?
Docker automatically generates an internal DNS network where services can be discovered by name (the name postgres comes from docker-compose.yml).

[King_Samuel_David]

@Emanuel_Maricic

Hello,

Also is this postgres for the db of n8n or is it a seperate postgres for rag / storage?

You can implement into the same docker compose for n8n also see here for examples,

Ultimate n8n Dev Container (with Debugging, Monitoring & Observability) Dockers

Hey n8n fam , I wanted to share my Docker-based full dev container setup I’ve been building to make working with n8n smoother, especially when working with queues, databases, and performance tuning. Key Features n8n + n8n-worker (with queue mode support) Disabled in Dockerfile, enable by removing comments PostgreSQL + pgAdmin Redis + RedisInsight Bull Board for queue debugging Prome…

Hope this helps,

Samuel

[Emanuel_Maricic]

version: "3.8"

services:
  postgres:
    image: postgres
    ports:
      - "5435:5432"
    environment:
      - POSTGRES_DB=postgres
      - POSTGRES_USER=postgres
      - POSTGRES_PASSWORD=postgres
    networks:
      - n8n-network

networks:
  n8n-network:
    driver: bridge

I’m trying to configure it with this simple docker configuration
when I try to set host as ‘postgres’ i get an error
**

**
container is up and running

[King_Samuel_David]

@Emanuel_Maricic

Did you resolve it? Where you have localhost as the host, replace with the actual container name (postgres) or from the screenshot (n8n-postgres-1)

Best regards,

Samuel