SAC Automation, Scripting, and Virtualization 5

Question 1

What is the function of an Ansible 'handler' in a playbook?

Accepted Answer

A task triggered by a 'notify' directive that runs only once at the end of a play if notified

Answer

Handlers are special tasks that execute after all tasks complete, but only if notified by at least one changed task.

Question 2

Which Python library is commonly used to run shell commands from within a Python script and capture their output?

Accepted Answer

subprocess

Answer

The subprocess module (especially subprocess.run() and subprocess.Popen()) executes external commands and captures stdout/stderr.

Question 3

In KVM/QEMU virtualization, which tool provides a command-line interface for managing virtual machines, networks, and storage pools?

Accepted Answer

virsh

Answer

virsh is the command-line interface to the libvirt daemon, allowing admins to start, stop, snapshot, and configure VMs.

Question 4

A sysadmin wants a script to process only lines containing the word 'FAILED' in a log file. Which command achieves this most efficiently?

Accepted Answer

grep 'FAILED' logfile

Answer

Calling grep directly on the file is more efficient than piping cat output, avoiding a useless use of cat (UUOC).

Question 5

What does 'overcommitment' mean in the context of virtual machine memory management?

Accepted Answer

Assigning more total VM RAM than the physical host actually has installed

Answer

Memory overcommitment relies on techniques like ballooning and transparent huge pages to allow total VM RAM to exceed physical RAM.

(SAC) System Administration Certification Practice Test