# Timeshift Snapshot and Rollback Guide

## Overview

Timeshift is a system restore utility that creates snapshots of your system before Ansible playbook execution.
This allows you to easily rollback if something goes wrong during configuration changes.

## How It Works

When you run a playbook, the Timeshift role automatically:
1. Checks if Timeshift is installed (installs if missing)
2. Creates a snapshot before making any changes
3. Tags the snapshot with "ansible" and "pre-playbook" for easy identification

## Usage

### Automatic Snapshots

Snapshots are created automatically when running playbooks:

```bash
# Run playbook - snapshot created automatically
make dev HOST=dev02

# Or run only snapshot creation
make timeshift-snapshot HOST=dev02
```

### List Snapshots

```bash
# List all snapshots on a host
make timeshift-list HOST=dev02

# Or manually on the host
ssh ladmin@192.168.20.28 "sudo timeshift --list"
```

### Restore from Snapshot

```bash
# Restore from a specific snapshot
make timeshift-restore HOST=dev02 SNAPSHOT=2025-12-17_21-30-00

# The command will:
# 1. Show available snapshots if SNAPSHOT is not provided
# 2. Ask for confirmation before restoring
# 3. Restore the system to that snapshot
```

### Manual Snapshot

```bash
# Create snapshot manually on host
ssh ladmin@192.168.20.28
sudo timeshift --create --comments "Manual snapshot before manual changes"
```

### Manual Restore

```bash
# SSH to host
ssh ladmin@192.168.20.28

# List snapshots
sudo timeshift --list

# Restore (interactive)
sudo timeshift --restore

# Or restore specific snapshot (non-interactive)
sudo timeshift --restore --snapshot '2025-12-17_21-30-00' --scripted
```

## Configuration

### Disable Auto-Snapshots

If you don't want automatic snapshots, disable them in `host_vars` or `group_vars`:

```yaml
# inventories/production/host_vars/dev02.yml
timeshift_auto_snapshot: false
```

### Customize Snapshot Settings

```yaml
# inventories/production/group_vars/dev/main.yml
timeshift_snapshot_description: "Pre-deployment snapshot"
timeshift_snapshot_tags: ["ansible", "deployment"]
timeshift_keep_daily: 7
timeshift_keep_weekly: 4
timeshift_keep_monthly: 6
```

## Important Notes

### Disk Space

- Snapshots require significant disk space (typically 10-50% of system size)
- RSYNC snapshots are larger but work on any filesystem
- BTRFS snapshots are smaller but require BTRFS filesystem
- Monitor disk usage: `df -h /timeshift`

### What Gets Backed Up

By default, Timeshift backs up:
- ✅ System files (`/etc`, `/usr`, `/boot`, etc.)
- ✅ System configuration
- ❌ User home directories (`/home`) - excluded by default
- ❌ User data

### Recovery Process

1. **Boot from recovery** (if system won't boot):
   - Boot from live USB
   - Install Timeshift: `sudo apt install timeshift`
   - Run: `sudo timeshift --restore`

2. **Restore from running system**:
   - SSH to host
   - Run: `sudo timeshift --restore`
   - Select snapshot and confirm

### Best Practices

1. **Always create snapshots before major changes**
   ```bash
   make timeshift-snapshot HOST=dev02
   make dev HOST=dev02
   ```

2. **Test rollback process** before you need it
   ```bash
   # Create test snapshot
   make timeshift-snapshot HOST=dev02
   
   # Make a test change
   # ...
   
   # Practice restoring
   make timeshift-list HOST=dev02
   make timeshift-restore HOST=dev02 SNAPSHOT=<test-snapshot>
   ```

3. **Monitor snapshot disk usage**
   ```bash
   ssh ladmin@192.168.20.28 "df -h /timeshift"
   ```

4. **Clean up old snapshots** if needed
   ```bash
   ssh ladmin@192.168.20.28 "sudo timeshift --delete --snapshot 'OLD-SNAPSHOT'"
   ```

## Troubleshooting

### Snapshot Creation Fails

```bash
# Check Timeshift status
ssh ladmin@192.168.20.28 "sudo timeshift --list"

# Check disk space
ssh ladmin@192.168.20.28 "df -h"

# Check Timeshift logs
ssh ladmin@192.168.20.28 "sudo journalctl -u timeshift"
```

### Restore Fails

- Ensure you have enough disk space
- Check that snapshot still exists: `sudo timeshift --list`
- Try booting from recovery media if system won't boot

### Disk Full

```bash
# List snapshots
sudo timeshift --list

# Delete old snapshots
sudo timeshift --delete --snapshot 'OLD-SNAPSHOT'

# Or configure retention in group_vars
timeshift_keep_daily: 3  # Reduce from 7
timeshift_keep_weekly: 2  # Reduce from 4
```

## Integration with Ansible

The Timeshift role is automatically included in the development playbook and runs first to create snapshots before any changes are made.
This ensures you always have a restore point.

```yaml
# playbooks/development.yml
roles:
  - {role: timeshift, tags: ['timeshift', 'snapshot']}  # Runs first
  - {role: base}
  - {role: development}
  # ... other roles
```

## See Also

- [Timeshift Documentation](https://github.com/teejee2008/timeshift)
- [Ansible Vault Guide](./vault.md) - For securing passwords
- [Maintenance Guide](../reference/makefile.md) - For system maintenance