Backup & Disaster Recovery Flashcards

Which rsync option enables compression of data during transfer to reduce bandwidth usage?

Answer: -z

rsync -z compresses file data during the transfer, which reduces bandwidth at the cost of extra CPU usage on both endpoints.

When using 'rsync --delete', what happens to files at the destination that no longer exist at the source?

Answer: They are deleted from the destination

rsync --delete removes files from the destination that are no longer present at the source, keeping the destination a true mirror.

Which command would you use to restore a specific file 'etc/passwd' from a tar archive 'backup.tar.gz'?

Answer: tar -xzf backup.tar.gz etc/passwd

tar -xzf extracts (-x) from a gzip-compressed (-z) archive file (-f), and specifying 'etc/passwd' restores only that file.

A disaster recovery plan calls for a 'warm standby' site. What best describes this?

Answer: A site with hardware and software pre-configured but not actively processing live traffic

A warm standby site has hardware and software ready but runs on recent (not real-time) data and requires some activation time before it can serve production traffic.

What is the purpose of the 'mt' command in Linux backup operations?

Answer: Control magnetic tape drive operations such as rewind, eject, and seek

The mt (magnetic tape) command sends control operations to a tape drive, such as rewinding, forwarding, ejecting, or seeking to a specific position.

Which /proc file provides information useful for identifying mounted filesystems that should be included in a backup plan?

Answer: /proc/mounts

/proc/mounts lists all currently mounted filesystems including their mount points, device, and options, helping identify what must be backed up.

Which option in crontab syntax schedules a backup job to run at 2:30 AM every Sunday?

Answer: 30 2 * * 0

Crontab fields are minute hour day month weekday; '30 2 * * 0' means minute 30, hour 2, any day/month, weekday 0 (Sunday).