Description

docker compose up fails when trying to start PostgreSQL. The container exits with an error about data directory format incompatibility.

Steps to Reproduce

1. Run docker compose build
2. Run docker compose up
3. Watch postgres-db container fail

Error Message

Root Cause

The docker-compose.yml specifies image: postgres with no version tag. Docker pulls the latest PostgreSQL (currently 18). PostgreSQL 18 changed the expected data directory path from /var/lib/postgresql/data to /var/lib/postgresql, causing a mismatch.

Solution

Either:

1. Pin PostgreSQL to 16: image: postgres:16
2. Update the volume mount path to match PostgreSQL 18 expectations: /var/lib/postgresql

I can submit a PR with the fix if you decide which approach is preferred.

Environment

• Docker version: 28.3.3
• Docker Compose: v2

References

• https://hub.docker.com/_/postgres (PostgreSQL 18 release notes)
• Change PGDATA in 18+ to /var/lib/postgresql/MAJOR/docker docker-library/postgres#1259