CompTIA Linux+ (XK0-006) — All Questions

In a bash script, which variable holds the exit status of the most recently executed command?

• a.$#
• b.$?✓
• c.$!
• d.$0

'$?' contains the exit status of the last command, where 0 means success and non-zero indicates an error. '$#' is the argument count, '$!' is the PID of the last background job, and '$0' is the script name.

Which cron schedule expression runs a job every day at 2:30 AM?

• a.30 2 * * *✓
• b.* 2 30 * *
• c.2 30 * * *
• d.30 2 * * 0

Cron fields are minute, hour, day-of-month, month, day-of-week, so '30 2 * * *' means minute 30 of hour 2 every day. '30 2 * * 0' would restrict it to Sundays, and the other orderings misplace the minute and hour fields.

In Ansible, which characteristic describes a well-written task that can run repeatedly without changing the result after the first successful run?

• a.Imperative
• b.Ephemeral
• c.Idempotent✓
• d.Stateful

Idempotency means applying the same task multiple times yields the same end state, so Ansible only makes changes when the system differs from the desired state. This is a core principle of infrastructure-as-code that prevents unintended repeated modifications.