305-300 Practice Test 2 — 10 Questions

Question 1

Which TWO commands are used to manage images in Docker?

Accepted Answer

docker tag. 'docker build' creates images, and 'docker tag' renames/labels them.

Answer

docker run

Answer

docker create

Answer

docker attach

Question 2

You need to create a snapshot of a QCOW2 disk image without stopping the virtual machine. Which qemu-img sub-command should be used?

Accepted Answer

virsh snapshot-create-as --domain vm_name --name snap1 --disk-only. qemu-img snapshot -c creates a snapshot, but it should only be done on offline images. For live snapshots, virsh snapshot-create is required.

Answer

qemu-img create -f qcow2 -b image.qcow2 snapshot.qcow2

Answer

qemu-img snapshot -c snapshot_name image.qcow2

Answer

virsh checkpoint-create vm_name

Question 3

Which command is used to display the XML configuration of a running VM domain named 'webserver'?

Accepted Answer

virsh dumpxml webserver. virsh dumpxml webserver outputs the XML definition of the specified domain.

Answer

virsh export webserver

Answer

virsh show-config webserver

Answer

virsh get-xml webserver

Question 4

What is the primary function of a Docker Registry?

Accepted Answer

To store and distribute images. A registry stores and distributes Docker images.

Answer

To build images

Answer

To run containers

Answer

To manage networking

Question 5

In a FreeBSD Jail, how can you ensure the jail starts automatically at boot?

Accepted Answer

Set jail_enable=YES in /etc/rc.conf. Setting 'jail_enable="YES"' in /etc/rc.conf is required for the jails subsystem to start.

Answer

Create a symlink in /etc/init.d

Answer

Use systemd

Answer

Add a cron job

Question 6

Which Docker command is used to display the resource usage (CPU, memory) of running containers?

Accepted Answer

docker stats. 'docker stats' provides a real-time stream of container resource usage statistics.

Answer

docker top

Answer

docker usage

Answer

docker info

Question 7

Which flag is used to run a container in the background?

Accepted Answer

-d. The -d or --detach flag runs the container in the background.

Answer

-t

Answer

-b

Answer

-i

Question 8

You are using a BSD Jail and want to limit the filesystem access of the jail to a specific directory tree. Which utility or configuration mechanism is primarily used to achieve this?

Accepted Answer

jail.conf path parameter. The 'path' configuration parameter in the jail.conf file defines the root directory of the jail.

Answer

mount -t nullfs

Answer

jail_root_dir

Answer

chroot

Question 9

When using 'docker-compose', which file format is used to define the services?

Accepted Answer

YAML. Docker Compose uses YAML files.

Answer

INI

Answer

XML

Answer

JSON

Question 10

When configuring a Docker volume that needs to be shared between multiple containers, which storage driver storage path is recommended to ensure persistent data availability if the host reboots?

Accepted Answer

-v /host/path:/container/path. Using a named volume or a bind mount to a host directory ensures persistence beyond the container lifecycle.

Answer

--link

Answer

--tmpfs

Answer

--volume-driver=none

Answer

--memory