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+# Docker Volumes Reference
+
+## Volume Types
+
+### Named Volumes (Recommended)
+
+Managed by Docker, stored in `/var/lib/docker/volumes/`.
+
+```yaml
+volumes:
+  db-data:
+
+services:
+  db:
+    volumes:
+      - db-data:/var/lib/mysql
+```
+
+Benefits:
+- Portable across hosts
+- Backup-friendly
+- No permission issues
+- Can use volume drivers (NFS, etc.)
+
+### Bind Mounts
+
+Direct host path mapping.
+
+```yaml
+services:
+  web:
+    volumes:
+      - ./config:/etc/app/config:ro
+      - /host/data:/container/data
+```
+
+Benefits:
+- Direct file access from host
+- Development workflow (live reload)
+- Access to host files
+
+Drawbacks:
+- Host-dependent paths
+- Permission issues possible
+- Less portable
+
+### tmpfs Mounts
+
+In-memory storage (Linux only).
+
+```yaml
+services:
+  app:
+    tmpfs:
+      - /tmp
+      - /run:size=100m
+```
+
+Benefits:
+- Fast (RAM-based)
+- Secure (not persisted)
+- Good for secrets, cache
+
+## Volume Options
+
+### Read-Only
+
+```yaml
+volumes:
+  - ./config:/etc/app/config:ro
+```
+
+### Bind Propagation
+
+```yaml
+volumes:
+  - type: bind
+    source: ./data
+    target: /data
+    bind:
+      propagation: rslave
+```
+
+### Volume Driver Options
+
+```yaml
+volumes:
+  nfs-data:
+    driver: local
+    driver_opts:
+      type: nfs
+      o: addr=192.168.1.100,rw
+      device: ":/export/data"
+```
+
+## Common Patterns
+
+### Database Data
+
+```yaml
+services:
+  postgres:
+    image: postgres:15
+    volumes:
+      - pgdata:/var/lib/postgresql/data
+    environment:
+      POSTGRES_PASSWORD: secret
+
+volumes:
+  pgdata:
+```
+
+### Configuration Files
+
+```yaml
+services:
+  nginx:
+    image: nginx:alpine
+    volumes:
+      - ./nginx.conf:/etc/nginx/nginx.conf:ro
+      - ./html:/usr/share/nginx/html:ro
+```
+
+### Shared Data Between Services
+
+```yaml
+services:
+  app:
+    volumes:
+      - shared:/data
+
+  worker:
+    volumes:
+      - shared:/data
+
+volumes:
+  shared:
+```
+
+### Log Persistence
+
+```yaml
+services:
+  app:
+    volumes:
+      - logs:/var/log/app
+
+volumes:
+  logs:
+```
+
+## Backup and Restore
+
+### Backup Named Volume
+
+```bash
+# Create backup
+docker run --rm \
+  -v myvolume:/source:ro \
+  -v $(pwd):/backup \
+  alpine tar czf /backup/myvolume.tar.gz -C /source .
+
+# Restore backup
+docker run --rm \
+  -v myvolume:/target \
+  -v $(pwd):/backup \
+  alpine tar xzf /backup/myvolume.tar.gz -C /target
+```
+
+### Copy Files from Volume
+
+```bash
+docker cp <container>:/path/to/file ./local-file
+```
+
+## Volume Management
+
+```bash
+# List volumes
+docker volume ls
+
+# Inspect volume
+docker volume inspect <volume>
+
+# Remove unused volumes
+docker volume prune
+
+# Remove specific volume
+docker volume rm <volume>
+
+# Create volume manually
+docker volume create --name myvolume
+```
+
+## Permissions
+
+### Common Permission Issues
+
+```bash
+# Check container user
+docker exec <container> id
+
+# Check volume permissions
+docker exec <container> ls -la /data
+```
+
+### Solutions
+
+```yaml
+# Run as specific user
+services:
+  app:
+    user: "1000:1000"
+    volumes:
+      - ./data:/data
+```
+
+Or fix host permissions:
+```bash
+chown -R 1000:1000 ./data
+```
+
+## Best Practices
+
+1. **Use named volumes for data** - More portable than bind mounts
+2. **Read-only when possible** - Use `:ro` for config files
+3. **Separate concerns** - Different volumes for data, config, logs
+4. **Backup strategy** - Plan for volume backup/restore
+5. **Don't store in image** - Data should be in volumes, not image layers
+6. **Use .dockerignore** - Exclude data directories from build context