PostgreSQL · infra · fg-0276

postgres:18 container fails to start or loses data when the volume is mounted at /var/lib/postgresql/data

error mounting "..." to rootfs at "/var/lib/postgresql/data": ... no such file or directory: unknown

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

From PostgreSQL 18 the official image sets PGDATA to /var/lib/postgresql/18/docker and declares the volume at /var/lib/postgresql, so a mount at the old data path is not where the server writes.

Fix

Mount the volume at /var/lib/postgresql for 18 and later. For existing data, move the files into an 18/docker subfolder after a proper upgrade, or keep the 17 tag until then.

Apply

services:
  db:
    image: postgres:18
    volumes:
      - pgdata:/var/lib/postgresql

Affects: Docker Official Image postgres 18 and later (September 2025)

Sources

• https://github.com/docker-library/docs/blob/master/postgres/content.md
• https://github.com/docker-library/postgres/issues/1364
• https://github.com/docker-library/postgres/issues/1370

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