Explanation
This command does create a swarm service that only listens on port 53 using the UDP protocol. The docker service create command creates a new service in a swarm cluster. The --name flag sets the name of the service.
The -p or --publish flag publishes a port or a range of ports to the swarm. The syntax for publishing a port is -p
<published-port>:<target-port>[/protocol]. The protocol can be tcp or udp. If no protocol is specified, tcp is used by default. In this case, the command publishes port 53 on the swarm and maps it to port 53 in the container using the udp protocol. Therefore, this command creates a swarm service that only listens on port 53 using the udp protocol. References: https://docs.docker.com/engine/reference/commandline/service_create/,
https://docs.docker.com/engine/reference/commandline/service_create/#publish-service-ports-externally-to-the-s

Explanation
The networkPolicy will not block this traffic because it does not apply to pods that have the tier: backend label. The networkPolicy only applies to pods that have the tier: frontend label, as specified by the podSelector field. Pods that have the tier: backend label are not affected by this networkPolicy and can receive traffic from any source.
References:
https://kubernetes.io/docs/concepts/services-networking/network-policies/#the-networkpolicy-resource

Explanation
Using kubectl logs deployment api does not display the events table for this object. The kubectl logs command shows the logs of a pod or a container in a pod, but it does not show the events related to the deployment object. To see the events table for this object, you need to use kubectl describe deployment api. References:
https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands#logs,
https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands#describe

Explanation
This
statement is correct about this health check definition. A health check is a feature that allows Docker to monitor the health status of a container by running a command in the container periodically. A health check has three parameters: test, interval, and retries. The test parameter specifies the command to run to check the health of the container. The interval parameter specifies how often to run the health check. The retries parameter specifies how many consecutive failures of the health check are needed to mark the container as unhealthy. In this case, the health check runs curl -f http://localhost/ || exit 1 every 10 seconds to test for app health. If this command fails three times in a row, the container is marked as unhealthy. References:
https://docs.docker.com/engine/reference/builder/#healthcheck,
https://docs.docker.com/engine/reference/run/#healthcheck

Explanation
These conditions are sufficient for Kubernetes to dynamically provision a persistentVolume, because a default storageClass provides the information needed to create a persistentVolume that matches the persistentVolumeClaim. According to the official documentation, if no storageClass is specified or requested, then the default one is used.
References: https://kubernetes.io/docs/concepts/storage/dynamic-provisioning/#defaulting-behavior