When opening a support case, it is often helpful to provide debugging information about your cluster to Red Hat Support.

The must-gather tool enables you to collect diagnostic information about your OpenShift Container Platform cluster, including virtual machines and other data related to container-native virtualization.

Container-native virtualization is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview/.

About the must-gather tool

The oc adm must-gather CLI command collects the information from your cluster that is most likely needed for debugging issues, such as:

  • Resource definitions

  • Audit logs

  • Service logs

You can specify one or more images when you run the command by including the --image argument. When you specify an image, the tool collects data related to that feature or product.

When you run oc adm must-gather, a new Pod is created on the cluster. The data is collected on that Pod and saved in a new directory that starts with must-gather.local. This directory is created in the current working directory.

About collecting container-native virtualization data

You can use the oc adm must-gather CLI command to collect information about your cluster, including features and objects associated with container-native virtualization:

  • The Hyperconverged Cluster Operator namespaces (and child objects)

  • All namespaces (and their child objects) that belong to any container-native virtualization resources

  • All container-native virtualization Custom Resource Definitions (CRDs)

  • All namespaces that contain virtual machines

  • All virtual machine definitions

To collect container-native virtualization data with must-gather, you must specify the container-native virtualization image: --image=registry.redhat.io/container-native-virtualization/cnv-must-gather-rhel8.

Gathering data about specific features

You can gather debugging information about specific features by using the oc adm must-gather CLI command with the --image or --image-stream argument. The must-gather tool supports multiple images, so you can gather data about more than one feature by running a single command.

Prerequisites
  • Access to the cluster as a user with the cluster-admin role.

  • The OpenShift Container Platform CLI (oc) installed.

Procedure
  1. Navigate to the directory where you want to store the must-gather data.

  2. Run the oc adm must-gather command with one or more --image or --image-stream arguments. For example, the following command gathers both the default cluster data and information specific to container-native virtualization:

    $ oc adm must-gather \
     --image-stream=openshift/must-gather \ (1)
     --image=registry.redhat.io/container-native-virtualization/cnv-must-gather-rhel8 (2)
    1 Default OpenShift Container Platform must-gather image
    2 Container-native virtualization must-gather image
  3. Create a compressed file from the must-gather directory that was just created in your working directory. For example, on a computer that uses a Linux operating system, run the following command:

    $ tar cvaf must-gather.tar.gz must-gather.local.5421342344627712289/ (1)
    1 Make sure to replace must-gather-local.5421342344627712289/ with the actual directory name.
  4. Attach the compressed file to your support case on the Red Hat Customer Portal.