EX188 Networking And Compose Practice Test 2 — 15 Questions

Question 1

You need to configure a container port mapping in Podman Compose so that host port 80 forwards to container port 8080. Which YAML syntax is correct under the service definition?

Accepted Answer

ports:
  - "80:8080". The 'ports' directive uses strings or lists in 'HOST:CONTAINER' format.

Answer

publish:
  - 80->8080

Answer

expose:
  - "80:8080"

Answer

ports:
  container: 8080
  host: 80

Question 2

In a Podman Compose file, how do you define a custom network and connect a service to it?

Accepted Answer

Define networks at the root level and reference them under each service configuration.. Compose files require a top-level 'networks:' section and service-level 'networks:' declarations.

Answer

Use the 'links:' directive inside the service block exclusively.

Answer

Add a 'network_mode' string directly pointing to an external shell script.

Answer

Configure networking exclusively via command-line environment variables.

Question 3

When inspecting the networking of a container using 'podman inspect', where is the IP address of the container located in the output JSON structure?

Accepted Answer

NetworkSettings.IPAddress. The NetworkSettings.IPAddress field contains the IPv4 address assigned to the container on its default network.

Answer

HostConfig.PortBindings.IP

Answer

Config.Network.IP

Answer

State.Networking.Address

Question 4

You wish to connect an already running container to an existing custom Podman network named 'mynet'. Which command should you use?

Accepted Answer

podman network connect mynet mycontainer. 'podman network connect' attaches a running or stopped container to a specified network.

Answer

podman network attach mynet mycontainer

Answer

podman container network-add mynet mycontainer

Answer

podman network join mynet mycontainer

Question 5

Which flag allows you to publish a container port to a random ephemeral port on the host interface?

Accepted Answer

-P. Using -P or --publish-all publishes all exposed ports to random high-numbered ports on the host.

Answer

-p random

Answer

-p 0:8080

Answer

--port dynamic

Question 6

How do you disconnect a running container from a custom network named 'mynet'?

Accepted Answer

podman network disconnect mynet mycontainer. 'podman network disconnect' removes a container from a specified network.

Answer

podman container disconnect mynet mycontainer

Answer

podman network remove mynet mycontainer

Answer

podman network detach mynet mycontainer

Question 7

You need to troubleshoot name resolution between containers on a custom network. Which backend service does Podman utilize by default for container DNS resolution in modern rootless setups?

Accepted Answer

aardvark-dns. Aardvark-dns is the authoritative DNS server used alongside netavark for Podman networking.

Answer

nscd

Answer

dnsmasq

Answer

bind9

Question 8

You want to create a Podman network with a specific subnet and gateway. Which command correctly specifies these parameters?

Accepted Answer

podman network create --subnet 192.168.200.0/24 --gateway 192.168.200.1 customnet. 'podman network create --subnet 192.168.200.0/24 --gateway 192.168.200.1 customnet' sets up custom IPAM settings.

Answer

podman network create --ip-range 192.168.200.0/24 customnet

Answer

podman network new --subnet=192.168.200.0/24 customnet

Answer

podman network create customnet --network 192.168.200.0/24

Question 9

Which command removes all unused Podman networks that are not currently connected to any containers?

Accepted Answer

podman network prune. 'podman network prune' deletes unused networks.

Answer

podman network clean

Answer

podman network rm --unused

Answer

podman prune networks

Question 10

You are writing a Podman Compose file and want to ensure a service depends on another service being fully started before it initializes. Which directive should you use?

Accepted Answer

depends_on. The 'depends_on' directive controls startup order of services in compose files.

Answer

requires

Answer

wait_for

Answer

links_to

Question 11

When generating a Kubernetes Pod YAML from a Podman container using 'podman generate kubernetes', how are published ports mapped into the resulting Kubernetes manifest?

Accepted Answer

They are translated into container port definitions within the containers spec array.. Published ports are translated into container ports inside the pod specification and exposed via service/ports specifications depending on options.

Answer

They are converted into host-level iptables rules embedded in annotations.

Answer

They are ignored entirely and must be added manually.

Answer

They cause the generation command to fail with a port conflict error.

Question 12

You need to inspect the network traffic of a container by capturing packets on its virtual interface. Where can you find the host-side veth interface name associated with a running container?

Accepted Answer

In the container's network inspection output under network interface details.. Inspecting the network settings or container JSON reveals the interface name or network details, or using 'podman inspect' with network settings.

Answer

It is always named 'eth0' on the host system.

Answer

In the /etc/resolv.conf file inside the container.

Answer

In the systemd journal logs exclusively.

Question 13

You have created a Podman pod and want to launch two containers inside this pod so they share the same network namespace. How do you specify this during container creation?

Accepted Answer

podman run --pod mypod -d myimage. Using '--pod <pod_name>' places the new container inside an existing pod, sharing its network, IPC, and UTS namespaces.

Answer

podman run --share-namespace mypod -d myimage

Answer

podman pod connect mypod myimage

Answer

podman run --network pod:mypod -d myimage

Question 14

How do you check the logs of all services managed by a Podman Compose file?

Accepted Answer

podman-compose logs. 'podman-compose logs' displays log output from all services defined in the compose file.

Answer

podman-compose monitor

Answer

podman-compose output

Answer

podman logs --compose

Question 15

Which environment file option can be used in a Podman Compose file to automatically load environment variables for service configuration?

Accepted Answer

env_file. The 'env_file' directive allows passing a .env file into containers or using them for interpolation.

Answer

environment_source

Answer

variables_file

Answer

load_env