AltarDocker — Backup

AltarDocker — Backup & Restore Guide

Complete guide for backing up and restoring MongoDB and MinIO data.

MongoDB

Install MongoDB Database Tools

mongodump and mongorestore are part of MongoDB Database Tools. They are not included in MongoDB by default and must be installed separately.

Note: If you use the Docker container methods below, you don’t need to install these tools locally — they’re already available inside the mongo container.

Ubuntu/Debian:

# Import MongoDB public GPG key
curl -fsSL https://www.mongodb.org/static/pgp/server-6.0.asc | sudo gpg -o /usr/share/keyrings/mongodb-server-6.0.gpg --dearmor

# Add MongoDB repository
echo "deb [ signed-by=/usr/share/keyrings/mongodb-server-6.0.gpg ] https://repo.mongodb.org/apt/ubuntu jammy/mongodb-org/6.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-6.0.list

# Install database tools
sudo apt update
sudo apt install mongodb-database-tools

macOS (Homebrew):

brew tap mongodb/brew
brew install mongodb-database-tools

Windows:

  1. Download from: https://www.mongodb.com/try/download/database-tools
  2. Extract the ZIP file
  3. Add the bin folder to your PATH, or copy the executables to a folder already in PATH

Verify installation:

mongodump --version
mongorestore --version

Dump (Backup)

From Docker container

# Dump entire database to local folder
docker exec mongo_altar mongodump --db sacred --out /data/db/backup

# Copy backup from container to host
docker cp mongo_altar:/data/db/backup ./mongo_backup

From host (if mongodump is installed locally)

mongodump --host localhost --port 27017 --db sacred --out ./mongo_backup

With authentication

mongodump --host localhost --port 27017 \
  --username YOUR_USER \
  --password YOUR_PASSWORD \
  --authenticationDatabase admin \
  --db sacred \
  --out ./mongo_backup

Restore

To Docker container

# Copy backup to container
docker cp ./mongo_backup mongo_altar:/data/db/backup

# Restore from backup
docker exec mongo_altar mongorestore --db sacred /data/db/backup/sacred

From host (if mongorestore is installed locally)

mongorestore --host localhost --port 27017 --db [database_name] [/path/to/backup]

With authentication

mongorestore --host localhost --port 27017 \
  --username YOUR_USER \
  --password YOUR_PASSWORD \
  --authenticationDatabase admin \
  --db sacred \
  ./mongo_backup/sacred

Drop existing data before restore

Add --drop to remove existing collections before restoring:

docker exec mongo_altar mongorestore --drop --db sacred /data/db/backup/sacred

MinIO

MinIO stores data as files on disk. You can back up using standard file tools or the MinIO client (mc).

Option 1: Direct file copy (simplest)

Since MinIO data is mounted to ./data/minio/ by default, you can simply copy the folder:

Backup

# Stop MinIO first to ensure consistency (optional but recommended)
docker compose --profile minio stop minio

# Copy data folder
cp -r ./data/minio ./minio_backup

# Restart MinIO
docker compose --profile minio start minio

Restore

# Stop MinIO
docker compose --profile minio stop minio

# Restore data folder
rm -rf ./data/minio
cp -r ./minio_backup ./data/minio

# Restart MinIO
docker compose --profile minio start minio

Option 2: Using MinIO Client (mc)

The MinIO client provides more control and can sync between MinIO instances.

Install MinIO Client

Linux/macOS:

curl https://dl.min.io/client/mc/release/linux-amd64/mc -o mc
chmod +x mc
sudo mv mc /usr/local/bin/

Windows (PowerShell):

Invoke-WebRequest -Uri "https://dl.min.io/client/mc/release/windows-amd64/mc.exe" -OutFile "mc.exe"

Configure alias

mc alias set altar http://localhost:9000 minio_admin changeme123

Backup (mirror to local folder)

# Mirror entire MinIO server to local backup
mc mirror altar/ ./minio_backup/

Restore (mirror from local folder)

# Mirror local backup to MinIO server
mc mirror ./minio_backup/ altar/

Sync specific bucket

# Backup single bucket
mc mirror altar/my-bucket ./minio_backup/my-bucket

# Restore single bucket
mc mirror ./minio_backup/my-bucket altar/my-bucket

Automated Backup Script (Linux)

Create a script to back up both MongoDB and MinIO:

#!/bin/bash
# backup_altar.sh

set -e

BACKUP_DIR="/path/to/backups"
DATE_STR=$(date +%Y-%m-%d_%H-%M)
BACKUP_PATH="$BACKUP_DIR/$DATE_STR"

mkdir -p "$BACKUP_PATH"

echo "=== Backing up MongoDB ==="
docker exec mongo_altar mongodump --db sacred --out /data/db/backup
docker cp mongo_altar:/data/db/backup "$BACKUP_PATH/mongo"
docker exec mongo_altar rm -rf /data/db/backup

echo "=== Backing up MinIO ==="
# Option A: Direct copy (uncomment if using)
# cp -r ./data/minio "$BACKUP_PATH/minio"

# Option B: Using mc (uncomment if using)
# mc mirror altar/ "$BACKUP_PATH/minio/"

echo "=== Backup complete: $BACKUP_PATH ==="

# Keep only last 7 backups
cd "$BACKUP_DIR"
ls -dt */ | tail -n +8 | xargs -d '\n' rm -rf 2>/dev/null || true

Make executable and schedule:

chmod +x backup_altar.sh

# Add to crontab (daily at 3am)
crontab -e

Add this line:

0 3 * * * /path/to/backup_altar.sh >> /path/to/backup.log 2>&1

Restore Script (Linux)

#!/bin/bash
# restore_altar.sh

set -e

if [ -z "$1" ]; then
    echo "Usage: ./restore_altar.sh /path/to/backup/2025-01-08_03-00"
    exit 1
fi

BACKUP_PATH="$1"

if [ ! -d "$BACKUP_PATH" ]; then
    echo "Error: Backup directory not found: $BACKUP_PATH"
    exit 1
fi

echo "=== Restoring from: $BACKUP_PATH ==="

if [ -d "$BACKUP_PATH/mongo" ]; then
    echo "=== Restoring MongoDB ==="
    docker cp "$BACKUP_PATH/mongo" mongo_altar:/data/db/restore
    docker exec mongo_altar mongorestore --drop --db sacred /data/db/restore/sacred
    docker exec mongo_altar rm -rf /data/db/restore
fi

if [ -d "$BACKUP_PATH/minio" ]; then
    echo "=== Restoring MinIO ==="
    # Option A: Direct copy
    # docker compose --profile minio stop minio
    # rm -rf ./data/minio
    # cp -r "$BACKUP_PATH/minio" ./data/minio
    # docker compose --profile minio start minio

    # Option B: Using mc
    # mc mirror "$BACKUP_PATH/minio/" altar/
    echo "MinIO restore: uncomment preferred method in script"
fi

echo "=== Restore complete ==="

Tips

  • Test your backups regularly by restoring to a test environment
  • Store backups off-site (cloud storage, external drive, different server)
  • Document your backup schedule and retention policy
  • MongoDB: Use --gzip flag to compress dumps: mongodump --gzip --db sacred --out ./backup
  • MinIO: The mc mirror command supports --overwrite and --remove flags for exact mirroring