Data Backup and Recovery Flashcards

A company performs a full backup every Sunday. On Wednesday, the system crashes. Using a differential backup from Tuesday, how many backup sets are required to restore the data?

Answer: The Sunday full backup and the Tuesday differential backup.

A differential backup contains all changes made since the last full backup. Therefore, to restore the system, you only need the last full backup (Sunday) and the most recent differential backup (Tuesday).

Which data backup strategy involves copying only the data that has changed since the last backup of any type, resulting in the smallest backup sizes and fastest backup times?

Answer: Incremental backup

An incremental backup only copies data that has changed since the last backup, whether it was a full or another incremental backup. This makes the individual backup files smaller and the process faster compared to full or differential backups.

A user follows the '3-2-1 rule' for their critical photos. They have the original files on their laptop, a copy on an external hard drive stored in their desk, and another copy uploaded to a cloud storage service. Which part of the rule does the cloud storage service primarily fulfill?

Answer: Maintaining one off-site copy

The 3-2-1 backup rule recommends having three copies of your data on two different types of media, with one copy stored off-site. The cloud storage service acts as the off-site copy, protecting the data from local disasters like fire, flood, or theft that could destroy both the laptop and the local external hard drive.

A business determines that it cannot afford to lose more than 4 hours of transaction data in the event of a server failure. This 4-hour tolerance for data loss is known as the:

Answer: Recovery Point Objective (RPO)

The Recovery Point Objective (RPO) refers to the maximum acceptable amount of data loss an organization can tolerate, measured in time. It dictates the minimum frequency for backups. The RTO, on the other hand, is about how quickly the system must be restored to operational status.

What is the most critical reason for regularly testing your data backups?

Answer: To verify that the data can be successfully restored.

The primary purpose of testing backups is to ensure their integrity and confirm that the data is recoverable in a real data loss scenario. A backup is useless if it is corrupted or incomplete and cannot be restored successfully.

A user is deciding between a local backup on an external hard drive and a cloud backup service. What is a primary advantage of using a cloud backup service over a local backup?

Answer: It provides inherent protection against local disasters like fire or flood.

Cloud backup services store data in remote data centers, providing geographic separation from the user's physical location. This is a significant advantage as it protects the backup data from local incidents such as fire, flood, or theft that could destroy both the original data and a local backup.