How to Ensure Docker Daemon Persistence during Switchover on Cisco Nexus 9500 Series Switches

C.

The correct answer is A. Change the Docker configuration to include the live restore option.

When using Docker on the Cisco Nexus 9500 Series Switches running Cisco NX-OS, it is important to ensure that Docker daemon persistence is maintained during switchover to the standby supervisor. This can be accomplished by configuring Docker to use the "live restore" option.

The "live restore" option is a Docker daemon configuration option that allows containers to be automatically restarted after a daemon restart or system reboot. When this option is enabled, Docker saves the state of running containers to disk, including open files, network connections, and process IDs (PIDs). This allows the Docker daemon to quickly restore the container's state when it is restarted.

To enable the live restore option, you can modify the Docker daemon configuration file on the Cisco Nexus 9500 Series Switches. The configuration file is typically located at /etc/docker/daemon.json.

To enable the live restore option, add the following line to the configuration file:

jsonCopy code
"live-restore": true 

After making this change, you can test the configuration by restarting the Docker daemon and verifying that running containers are automatically restored.

It's important to note that copying the dockerpart file manually to the standby supervisor (options B and C) is not a recommended solution for maintaining Docker daemon persistence during switchover. The dockerpart file is used by the Docker plugin to store persistent data, and manually copying it can result in data loss or corruption.

Finally, option D, "The system takes automatic action," is not a valid answer because Docker daemon persistence is not maintained automatically during switchover on the Cisco Nexus 9500 Series Switches running Cisco NX-OS. You must take proactive steps to configure Docker to use the live restore option.