When opening a support case, it is 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 OpenShift Virtualization.

For prompt support, supply diagnostic information for both OpenShift Container Platform and OpenShift Virtualization.

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 OpenShift Virtualization data

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

  • The Hyperconverged Cluster Operator namespaces (and child objects)

  • All namespaces (and their child objects) that belong to any OpenShift Virtualization resources

  • All OpenShift Virtualization Custom Resource Definitions (CRDs)

  • All namespaces that contain virtual machines

  • All virtual machine definitions

To collect OpenShift Virtualization data with must-gather, you must specify the OpenShift Virtualization image: --image=registry.redhat.io/container-native-virtualization/cnv-must-gather-rhel8:v2.4.1.

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.

To collect the default must-gather data in addition to specific feature data, add the --image-stream=openshift/must-gather argument.

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 OpenShift Virtualization:

    $ oc adm must-gather \
     --image-stream=openshift/must-gather \ (1)
     --image=registry.redhat.io/container-native-virtualization/cnv-must-gather-rhel8:v2.4.1 (2)
    
    1 The default OpenShift Container Platform must-gather image
    2 The must-gather image for OpenShift Virtualization
  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.