CSA Backup and Disaster Recovery 3 — Questions and Answers
Question 1: Which cloud storage class is most cost-effective for backup data that is rarely accessed but must be retrievable within minutes?
- Standard storage
- Intelligent-Tiering
- Glacier Instant Retrieval (or equivalent infrequent-access tier) (Correct answer)
- Glacier Deep Archive (or equivalent archive tier)
Correct answer: Glacier Instant Retrieval (or equivalent infrequent-access tier)
Infrequent-access tiers with instant retrieval offer low storage costs while still providing milliseconds-to-minutes access times.
Question 2: An administrator discovers that backup jobs have been completing successfully for months, but restores from those backups consistently fail. What is the most likely root cause?
- The backup window is too short
- Backup verification or integrity testing was never performed (Correct answer)
- The backup media is write-protected
- The backup software license expired
Correct answer: Backup verification or integrity testing was never performed
Backups should be regularly tested via restore drills; a backup that was never verified may be silently corrupted or incomplete.
Question 3: What does 'deduplication' accomplish in a backup system?
- Compresses backup files using ZIP algorithms
- Eliminates redundant data blocks so identical data is stored only once (Correct answer)
- Mirrors backup data to two separate locations simultaneously
- Splits large backup files into smaller chunks for easier transport
Correct answer: Eliminates redundant data blocks so identical data is stored only once
Deduplication identifies and stores only unique data blocks, significantly reducing backup storage requirements.
Question 4: Which disaster recovery metric defines the maximum age of data that can be lost during a recovery event?
- RTO
- RPO (Correct answer)
- MTTR
- SLA
Correct answer: RPO
RPO (Recovery Point Objective) specifies how far back in time recovery data can go, i.e., the maximum tolerable data loss window.
Question 5: A system administrator implements replication where data is written to the secondary site before the primary site confirms the write to the application. What type of replication is this?
- Asynchronous replication
- Synchronous replication (Correct answer)
- Snapshot-based replication
- Store-and-forward replication
Correct answer: Synchronous replication
Synchronous replication requires the secondary site to acknowledge the write before the primary confirms it, ensuring zero data loss but adding latency.
Question 6: What is the '3-2-1 backup rule'?
- Three backups taken daily, two weekly, one monthly
- Keep 3 copies of data, on 2 different media types, with 1 copy offsite (Correct answer)
- Three encryption layers, two authentication factors, one offsite key
- Three full backups, two differentials, one incremental per week
Correct answer: Keep 3 copies of data, on 2 different media types, with 1 copy offsite
The 3-2-1 rule is an industry best practice: 3 total copies, stored on 2 different media, with at least 1 copy kept offsite.
Question 7: Which backup method is most appropriate for capturing the state of a running virtual machine without shutting it down?
- Cold backup
- Snapshot-based backup (Correct answer)
- Archive backup
- Grandfather-Father-Son rotation
Correct answer: Snapshot-based backup
VM snapshots capture the in-memory state and disk at a point in time, allowing live VMs to be backed up without downtime.
CSA Backup and Disaster Recovery 3
Which cloud storage class is most cost-effective for backup data that is rarely accessed but must be retrievable within minutes?