305-300 Practice Test 6 — 10 Questions

Question 1

In the context of container orchestration, what is the role of a 'sidecar' container?

Accepted Answer

To provide auxiliary services like logging or monitoring for the main container. A sidecar container runs alongside the main application container in the same pod, providing auxiliary functionality such as log shipping, metrics collection, proxying, or configuration sync. It shares the pod's network namespace and lifecycle, augmenting rather than replacing the primary container. This is the canonical definition in Kubernetes and general container orchestration.

Answer

To act as a load balancer for the cluster

Answer

To store persistent data for the primary container

Answer

To run in a separate network namespace

Answer

To replace the main container when it crashes

Question 2

What does 'QEMU' stand for?

Accepted Answer

Quick Emulator. QEMU is an open-source emulator and virtualizer that performs hardware virtualization. The name 'QEMU' is an acronym for 'Quick Emulator', reflecting its original design goal of fast emulation of a complete computer system. It is widely used in conjunction with KVM (Kernel-based Virtual Machine) to provide full virtualization on Linux, and it can also run standalone as a pure emulator for cross-platform development and testing.

Answer

Quantum Emulator

Answer

Quick Execution Machine Utility

Answer

Quality Emulator

Question 3

Which TWO commands are used to manage images in Docker?

Accepted Answer

docker tag. docker tag (A) is correct because it manages images by creating a new reference/tag pointing to an existing image (docker tag SOURCE_IMAGE[:TAG] TARGET_IMAGE[:TAG]), which is an image-level operation. docker build (E) is correct because it manages images by constructing a new image from a Dockerfile and build context, producing an image stored in the local image cache. The other options operate on containers rather than images: docker run (B) creates and starts a container from an image, docker create (C) creates a container without starting it, and docker attach (D) attaches the local standard input/output/error streams to a running container's process.

Answer

docker run

Answer

docker create

Answer

docker attach

Question 4

Which Packer builder is most appropriate for creating an image specifically for Amazon Web Services (AWS)?

Accepted Answer

amazon-ebs. The amazon-ebs builder is Packer's native AWS builder that launches a temporary EC2 instance, provisions it, creates an EBS-backed AMI, and terminates the instance. It is the standard and most appropriate choice for producing AWS AMIs directly. The other builders target different platforms or artifact formats.

Answer

virtualbox-iso

Answer

qemu

Answer

docker

Question 5

What is the purpose of the 'virsh' tool?

Accepted Answer

To manage virtual domains. The 'virsh' tool is a command-line interface for managing libvirt-based virtual machines (domains). It allows administrators to create, start, stop, migrate, and configure virtual domains, as well as manage networks, storage pools, and other resources. It is not used for monitoring CPU temperature, compiling QEMU, or writing disk images to USB.

Answer

To monitor host CPU temperature

Answer

To compile QEMU

Answer

To write disk images to USB

Question 6

Which hypervisor type is considered 'Type 1' virtualization?

Accepted Answer

Xen. Xen is a Type 1 (bare-metal) hypervisor because it runs directly on the host hardware, with the hypervisor itself acting as the lowest software layer and managing guest domains. Type 1 hypervisors do not require a host OS underneath them, giving better performance and isolation for production virtualization. Xen's dom0 and domU architecture is a textbook example of this model.

Answer

VMware Workstation

Answer

VirtualBox

Answer

QEMU (user mode)

Question 7

How can you force a refresh of a libvirt storage pool named 'isos'?

Accepted Answer

virsh pool-refresh isos. 'virsh pool-refresh isos' is the exact libvirt command to refresh a storage pool named 'isos'. This command rescans the pool's underlying storage (e.g., a directory or LVM volume group) and updates libvirt's internal list of available volumes, making new files visible without restarting libvirtd.

Answer

virsh refresh-pool isos

Answer

virsh pool-update isos

Answer

virsh pool-reload isos

Question 8

You are configuring an OpenVZ container. Which command is used to set the hostname of the container from the host?

Accepted Answer

vzctl set CTID --hostname. The `vzctl set --hostname ` command sets the hostname of an OpenVZ container from the host. The `--hostname` option updates the container's configuration and applies the change, optionally with `--save` to persist it to the configuration file.

Answer

vzcfg

Answer

hostnamectl

Answer

openvz-edit

Question 9

Which THREE of the following are valid elements inside the <interface type='bridge'> block?

Accepted Answer

. Option A is correct because is the required child element that tells libvirt which host bridge the guest interface should be attached to, and it is valid inside . Option D is correct because is a valid child element that selects the emulated NIC model presented to the guest, with virtio being the paravirtualized option. Option E is correct because is a valid child element used to assign a specific MAC address to the guest interface. Options B and C are not valid here: and are not children of ; IP/gateway configuration belongs in the guest OS or in higher-level network definitions, not in the interface's bridge block.

Answer

Answer

Question 10

Which THREE of the following are common cloud-init modules?

Accepted Answer

packages. Option B (packages) is a standard cloud-init module that installs or upgrades packages on first boot by reading the packages and package_upgrade keys, so it is correct. Option C (runcmd) is a core cloud-init module that executes arbitrary shell commands listed under the runcmd key during the final boot stage, making it correct. Option E (users-groups) is the cloud-init module responsible for creating and configuring users and groups from the users and groups directives, so it is also correct. Options A (network-bridge) and D (disk-partition) are not cloud-init modules; networking is handled by modules such as network-config or the distro's network renderer, and partitioning is handled by modules like disk_setup and growpart, so neither belongs here.

Answer

network-bridge

Answer

disk-partition