Introduction
Disaster recovery (DR) is a critical aspect of system administration. This guide will help you create and implement a disaster recovery plan for your FreeBSD systems, ensuring business continuity in the face of unexpected events.
1. Risk Assessment
Identify potential threats to your FreeBSD systems:
- Hardware failures
- Software corruption
- Cyber attacks
- Natural disasters
- Human errors
For each risk, assess the potential impact and likelihood of occurrence.
2. Creating a Disaster Recovery Plan
2.1 Key Components
- Recovery Time Objective (RTO): Maximum acceptable downtime
- Recovery Point Objective (RPO): Maximum acceptable data loss
- Prioritized list of critical systems and data
- Backup and restoration procedures
- Emergency contact information
- Step-by-step recovery instructions
2.2 Documentation
Maintain detailed documentation of your FreeBSD system configuration:
# Document hardware specifications
$ dmidecode > /path/to/hardware_specs.txt
# Document software and package information
$ pkg info > /path/to/installed_packages.txt
# Document kernel configuration
$ cp /boot/kernel/kernel.config /path/to/kernel_config.txt
# Document network configuration
$ ifconfig -a > /path/to/network_config.txt
3. Backup Strategies
Implement a comprehensive backup strategy:
- Use ZFS snapshots for quick, point-in-time recovery
- Implement off-site backups using tools like rsync or ZFS send/receive
- Consider using versioned backups to protect against data corruption
4. System Recovery Procedures
4.1 Bare Metal Recovery
- Boot from FreeBSD installation media
- Set up disk partitions and file systems
- Restore from backup:
# For UFS file systems
$ restore -rf /path/to/backup.dump
# For ZFS file systems
$ zfs receive -F zroot < /path/to/zfs_backup
- Reinstall bootloader:
$ boot0cfg -B ada0
- Reboot and verify system functionality
4.2 Service-specific Recovery
Create procedures for recovering individual services, e.g.:
- Web server recovery
- Database server recovery
- Mail server recovery
5. Testing and Maintenance
Regularly test and update your disaster recovery plan:
- Conduct full DR drills at least annually
- Test backups by performing test restores
- Update DR documentation after system changes
- Train team members on DR procedures
6. High Availability Considerations
Implement high availability solutions to minimize downtime:
- Use CARP (Common Address Redundancy Protocol) for network redundancy
- Implement service clustering with tools like HAProxy
- Use ZFS replication for storage redundancy
7. Sample Disaster Recovery Checklist
| Step |
Action |
Responsible |
| 1 |
Assess the situation and declare disaster |
IT Manager |
| 2 |
Notify key stakeholders |
IT Manager |
| 3 |
Activate backup site if necessary |
System Administrator |
| 4 |
Begin system recovery procedures |
System Administrator |
| 5 |
Verify data integrity and system functionality |
System Administrator |
| 6 |
Switch operations to recovered systems |
IT Manager |
| 7 |
Conduct post-incident review |
IT Team |