Virtualization & Container Management Flashcards
7 cards from real LCA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Virtualization & Container Management flashcards as text
Which command displays all running and stopped Docker containers?
Answer: docker ps -a
The '-a' flag with 'docker ps' lists all containers regardless of state, including stopped ones.
In KVM virtualization, what file format natively supports snapshots, encryption, and compression?
Answer: qcow2
QCOW2 (QEMU Copy-On-Write v2) is KVM's native format supporting snapshots, encryption, and thin provisioning.
What is the purpose of the 'docker network create' command?
Answer: Create an isolated network for container communication
'docker network create' defines a new network that containers can join to communicate with each other in isolation.
Which libvirt tool is used to manage virtual networks from the command line?
Answer: virsh
virsh is the command-line interface for libvirt and can manage networks, domains, storage, and more.
A Dockerfile instruction 'COPY . /app' is run during which phase?
Answer: Image build
COPY and other Dockerfile instructions execute during 'docker build', creating image layers.
What does setting 'cpu_shares' on a cgroup accomplish for a virtual machine?
Answer: Sets the relative CPU scheduling weight
cpu_shares assigns a relative weight used by the scheduler when CPU contention occurs among cgroup members.
Which command saves a Docker image to a tar archive file?
Answer: docker save
'docker save' exports an image (including all layers and metadata) to a tar file for offline transfer.