TestOut Linux Pro Practice Test 2025 – Complete Exam Prep Guide

The command used to back up a directory with rsync is `rsync -av [source] [destination]`. This command efficiently synchronizes files and directories between the source and destination. The `-a` option stands for "archive," which preserves the original files' properties such as permissions, timestamps, and symbolic links, making it ideal for backups. The `-v` option enables verbose mode, providing detailed output of the operation being performed, which is useful for monitoring the backup process.

Using rsync for backups has several advantages, including its ability to only transfer the differences between files rather than the entire file set, optimizing bandwidth and time. This makes it highly effective for incremental backups, where only newly changed or added files are backed up after the initial full backup.

In contrast, the other options listed serve different purposes or are not suitable for backing up directories. Copying files using cp does not have the same level of efficiency or features for preserving file attributes as rsync. The tar command is typically used for archiving and compressing files but is not as efficient for synchronizing changes. The last option, "backup," is not a standard command in Linux for backup processes.