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+# Migration Guide
+
+This guide covers database migrations and version upgrades for ACC Server Manager.
+
+## Database Migrations
+
+The application handles database migrations automatically on startup. No manual intervention is required for most upgrades.
+
+### Automatic Migrations
+
+When you start the application:
+1. It checks the current database schema
+2. Applies any pending migrations
+3. Updates the schema version
+
+### Manual Migration (if needed)
+
+If automatic migration fails:
+
+```bash
+# Backup your database first
+copy acc.db acc_backup.db
+
+# Delete the database and let it recreate
+del acc.db
+
+# Start the application - it will create a fresh database
+./api.exe
+```
+
+## Upgrading ACC Server Manager
+
+### From v1.x to v2.x
+
+1. **Backup your data**
+   ```bash
+   copy acc.db acc_backup.db
+   copy .env .env.backup
+   ```
+
+2. **Stop the application**
+   ```bash
+   # If running as service
+   nssm stop "ACC Server Manager"
+   ```
+
+3. **Update the code**
+   ```bash
+   git pull
+   go build -o api.exe cmd/api/main.go
+   ```
+
+4. **Update configuration**
+   - Check `.env.example` for new required variables
+   - Run `.\scripts\generate-secrets.ps1` if needed
+
+5. **Start the application**
+   ```bash
+   ./api.exe
+   # Or restart service
+   nssm start "ACC Server Manager"
+   ```
+
+## Breaking Changes
+
+### v2.0
+- Changed from system_configs table to environment variables
+- Now use `STEAMCMD_PATH` and `NSSM_PATH` environment variables
+- UUID fields added to all tables (automatic migration)
+
+### v1.5
+- Authentication system overhaul
+- New permission system
+- Password requirements enforced
+
+## Data Backup
+
+### Regular Backups
+
+Create a scheduled task to backup your database:
+
+```powershell
+# PowerShell backup script
+$date = Get-Date -Format "yyyy-MM-dd"
+Copy-Item "acc.db" "backups\acc_$date.db"
+```
+
+### What to Backup
+
+- `acc.db` - Main database
+- `.env` - Configuration and secrets
+- `logs/` - Application logs (optional)
+- Server configuration files in each server directory
+
+## Rollback Procedure
+
+If an upgrade fails:
+
+1. Stop the application
+2. Restore the database: `copy acc_backup.db acc.db`
+3. Restore the configuration: `copy .env.backup .env`
+4. Use the previous binary version
+5. Start the application
+
+## Common Migration Issues
+
+### "Database locked"
+- Stop all instances of the application
+- Check for stuck processes
+
+### "Schema version mismatch"
+- Let automatic migration complete
+- Don't interrupt during migration
+
+### "Missing columns"
+- Database migration was interrupted
+- Restore from backup and retry
+
+## Best Practices
+
+1. **Always backup before upgrading**
+2. **Test upgrades in a non-production environment first**
+3. **Read release notes for breaking changes**
+4. **Keep the last working version's binary**
+5. **Monitor logs during first startup after upgrade**