How to Backup and Restore a Dockerized PostgreSQL Database

PostgreSQL is one of the most popular open-source relational database systems, widely used in modern applications. When running PostgreSQL inside Docker, managing backups and restores becomes a critical task to ensure data safety, especially in production environments.

In this blog, we’ll cover simple and reliable methods to backup and restore a Dockerized PostgreSQL database using built-in PostgreSQL tools like pg_dump and pg_restore.

Table of Contents

✅ Why Backup and Restore Matter

Protect against accidental data loss or corruption.
Migrate data between environments (e.g., from development to production).
Restore data after container upgrades or failures.

✅ 1️⃣ Backup a PostgreSQL Database Running in Docker

Assuming you already have a running PostgreSQL container:

docker ps

Example output:

CONTAINER ID   IMAGE          COMMAND                  NAMES
a1b2c3d4e5f6   postgres:14   "docker-entrypoint.s…"   pg-database

Backup Command Using `pg_dump`

docker exec -t pg-database pg_dump -U postgres -F c my_database > backup.dump

pg-database: The container name.
-U postgres: PostgreSQL user.
-F c: Output in custom format (compressed).
my_database: Database name inside PostgreSQL.
The output is redirected to backup.dump on the host system.

Alternatively, you can run pg_dump interactively and copy the output elsewhere.

✅ 2️⃣ Restore a PostgreSQL Database into Docker

Assuming you want to restore from the backup.dump file into the same or a new container.

Option A – Into the Existing Container

cat backup.dump | docker exec -i pg-database pg_restore -U postgres -d my_database

This feeds the backup file into pg_restore inside the running container.
Ensure the target database exists or create it before restoring:

docker exec -it pg-database psql -U postgres -c "CREATE DATABASE my_database;"

Option B – Into a New Container

docker run --rm -v $(pwd):/backup --name pg-restore -e POSTGRES_PASSWORD=mysecretpassword -d postgres:14

# Wait for the container to be ready, then restore:
cat backup.dump | docker exec -i pg-restore pg_restore -U postgres -d postgres

✅ 3️⃣ Automating Backup with Docker Volumes

For regular backups, it’s recommended to mount a volume:

version: '3.8'

services:
  postgres:
    image: postgres:14
    environment:
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: mysecretpassword
    volumes:
      - ./pgdata:/var/lib/postgresql/data
      - ./backups:/backups

Then, you can periodically run:

docker exec -t pg-database pg_dump -U postgres -F c my_database > ./backups/backup_$(date +%F).dump

This way, backups are persistent on the host machine.

✅ 4️⃣ Best Practices

Automate regular backups via cron jobs or external schedulers.
Store backups in separate storage (e.g., cloud storage) for disaster recovery.
Test restores regularly to verify backup integrity.
Use secure storage and encrypted backups if dealing with sensitive data.

✅ Conclusion

Backing up and restoring a Dockerized PostgreSQL database is easy using pg_dump and pg_restore inside Docker containers.
Whether for development, production, or disaster recovery, following these methods ensures your data remains safe, portable, and easy to manage.