LCA Backup & Disaster Recovery 3 — Questions and Answers
Question 1: Which dd command correctly creates a raw disk image of /dev/sda to a file called disk.img?
- dd if=/dev/sda of=disk.img (Correct answer)
- dd of=/dev/sda if=disk.img
- dd if=disk.img of=/dev/sda
- dd /dev/sda > disk.img bs=512
Correct answer: dd if=/dev/sda of=disk.img
dd reads from 'if' (input file) and writes to 'of' (output file); if=/dev/sda of=disk.img creates a byte-for-byte image of the disk.
Question 2: What does RTO stand for in disaster recovery planning?
- Recovery Time Objective (Correct answer)
- Restore Transfer Operation
- Redundant Transfer Option
- Recovery Transfer Output
Correct answer: Recovery Time Objective
RTO (Recovery Time Objective) is the maximum acceptable time to restore a system or service after a disaster.
Question 3: What does RPO stand for in disaster recovery planning?
- Recovery Point Objective (Correct answer)
- Restore Process Operation
- Redundant Point Option
- Recovery Protocol Output
Correct answer: Recovery Point Objective
RPO (Recovery Point Objective) defines the maximum acceptable amount of data loss measured in time — how old the most recent backup can be.
Question 4: Which Bacula daemon runs on the backup client and is responsible for reading/writing data on the client system?
- bacula-fd (File Daemon) (Correct answer)
- bacula-sd (Storage Daemon)
- bacula-dir (Director)
- bacula-mon (Monitor)
Correct answer: bacula-fd (File Daemon)
The Bacula File Daemon (bacula-fd) runs on each client and handles local file I/O during backup and restore operations.
Question 5: A sysadmin wants to verify a backup tape is readable without fully restoring it. Which tar option lists archive contents without extraction?
- -t (Correct answer)
- -x
- -c
- -d
Correct answer: -t
tar -t (--list) reads the archive and displays its contents without extracting any files, useful for verifying tape readability.
Question 6: Which feature of LVM is commonly used to enable consistent online backups of a running system?
- LVM snapshots (Correct answer)
- LVM mirroring
- LVM thin provisioning
- LVM striping
Correct answer: LVM snapshots
LVM snapshots create a point-in-time copy of a logical volume that can be backed up while the source volume remains online and in use.
Question 7: What is the 3-2-1 backup rule?
- 3 copies of data, on 2 different media types, with 1 offsite copy (Correct answer)
- 3 daily backups, 2 weekly, 1 monthly
- 3 full backups, 2 incremental, 1 differential per week
- 3 servers, 2 SANs, 1 cloud provider
Correct answer: 3 copies of data, on 2 different media types, with 1 offsite copy
The 3-2-1 rule is a best practice: keep 3 total copies of data, stored on 2 different media types, with at least 1 copy stored offsite.
LCA Backup & Disaster Recovery 3
Which dd command correctly creates a raw disk image of /dev/sda to a file called disk.img?