Docker Updated DCA Exam Questions and Answers by rueben

Docker allows the use of insecure registries through a specific configuration in the Docker daemon. By listing the insecure registries in the ‘daemon.json’ configuration file under the ‘insecure-registries’ key, Docker can interact with these registries even without a trusted TLS certificate1. This is particularly useful when setting up a private Docker registry1. However, it’s important to note that this configuration bypasses the security provided by TLS, and should be used with caution1.

The statement is incorrect because it does not mention the service name or the clusterIP address. Traffic sent to the IP of any pod with the label app: nginx on port 8080 will not be forwarded to port 80 in that pod, unless the traffic is coming from another pod within the same cluster that knows the pod IP. To access the service from outside the cluster, the traffic must be sent to the clusterIP address of the service, which is assigned by Kubernetes, and the port 8080 of the service, which is defined in the yaml file. The service will then forward the traffic to one of the selected pods on port 80.

To summarize, the correct statement should be:

Traffic sent to the clusterIP address of the service dca on port 8080 will be forwarded to port 80 in one of the pods with the label app: nginx.

The command docker run --log-driver=splunk for every container at run time will configure a Docker container to export container logs to the logging solution. The reason is that the --log-driver option specifies the logging driver for the container, which determines how the container logs are handled1. The splunk logging driver is a plugin that sends container logs to HTTP Event Collector in Splunk Enterprise and Splunk Cloud2. To use the splunk logging driver, you also need to provide some additional options with the --log-opt flag, such as the Splunk token, URL, source, sourcetype, index, etc2. For example, to run a container with the splunk logging driver and send the logs to a Splunk instance with the URL https://splunk.example.com:8088  and the token 176fabb6-7811-4b3a-8ba0-4d49302e50f2, you can use:

docker run --log-driver=splunk --log-opt splunk-token=176fabb6-7811-4b3a-8ba0-4d49302e50f2 --log-opt splunk-url=https://splunk.example.com:8088 ...

This way, you can configure a Docker container to export container logs to Splunk, which is a centralized logging solution. Alternatively, you can also configure the splunk logging driver as the default logging driver for the Docker daemon by setting the log-driver and log-opts keys in the daemon.json file and restarting Docker3. This will apply the splunk logging driver to all containers unless overridden by the --log-driver option. References:

• Configure logging drivers
• Splunk logging driver
• Set the logging driver for the Docker daemon