DMF Reliability Features
File system backup always required
- DMF interoperates with xfsdump/xfsrestore
- Can minimize dump time - just transfers inodes/directories
Issue: metadata in three places
- Inodes, DMF database, MSP database
All database transactions are journaled
- Replay journals after unscheduled interrupt
- New database uses two-phase commit
Comprehensive auditing utility for DMF databases
- dmaudit, dmatvfy, dmdbcheck (new at DMF 2.5)
Ability to create multiple copies of migrated data
- Disaster recovery and backup
Media integrity checking and recovery