Creating a Docker Client

A Docker virtualization client is required for the following use cases:

  • To manage backup and recovery operations for containers and images running on a Docker host. If you have multiple hosts, you might need to create a different virtualization client for each one.

  • To create VM Lifecycle Policies.

You must create Docker clients on client computers installed with the Virtual Server Agent.

To perform backup operations, each virtualization client can include multiple proxies where the Virtual Server Agent is installed. The virtualization client also enables proxy teaming, enabling proxy failovers for fault tolerant backups. Using multiple proxies for each virtualization client makes it possible to perform a large number of backups in a limited backup window.

When you create a virtualization client, the Commvault software automatically creates an instance, a backup set, and a default subclient that can be used to protect all containers and images. You can create additional subclients to perform separate protection operations for different groups. For example, you can create different subclients for different protection levels, and use the default subclient to protect any remaining containers or images.

Before You Begin

  • Install the Virtual Server Agent (VSA) on a client computer. It is not required to install the VSA on Docker hosts. You can also install the VSA on other machines to create additional VSA proxies.

  • At least one VSA proxy is needed.

  • Identify the host name or IP address and a TCP port that can be used to access the host.

  • Obtain administrator user credentials.

  • Use the command line to start Docker on the ephemeral port that will be used to access the Docker host. For example, the following command starts Docker on port 40046:

    /usr/bin/dockerd -H tcp:// -H unix:///var/run/docker.sock

    The ephemeral port can be in the range 1024-65535.

    Note: The use of the docker daemon command to start Docker is deprecated, and the command will be removed in a future release of Docker.

  • Enable Docker VM Lifecycle Management on CommCell Console.

  • Enable Docker VM Lifecycle Management on Web Console.


  1. From the CommCell Browser, right-click Client Computers, and then click New Client > Virtualization > Docker.

    The Create Docker Client dialog box appears.

  2. Enter the client name, access key, and secret key:

    • Client Name: Type a name for the client that will appear in the CommCell Browser.

    • Docker host and port: Type the fully qualified host name or IP address for the Docker host and the port number where Docker was started.

      Use the format host_name:port (for example,

  3. From the Storage Policy list, select a storage policy to associate with the virtualization client.

    The storage policy you select is also associated with the default subclient that is created automatically for the virtualization client.

  4. Click Add to select a proxy for backup.

  5. Add VSA proxies:

    1. Select one or more proxies from the Exclude list.

      The list displays all the UNIX clients that have the Virtual Server Agent installed and all the client groups. You can select one or more clients or client groups. When you select a client group, ensure that at least one client in the group has the Virtual Server Agent installed.

    2. Click Include or Include All.

      You can change the order of the proxies in the list by clicking up arrow or the down arrow. The first proxy in the list is the coordinator proxy.

    3. Click OK.

  6. Click OK to create the Docker client.