A.6. Manually Updating Hosts

You can use the yum command to update your hosts. Update your systems regularly, to ensure timely application of security and bug fixes.

Limitations

  • On RHVH, the update only preserves modified content in the /etc and /var directories. Modified data in other paths is overwritten during an update.
  • If migration is enabled at the cluster level, virtual machines are automatically migrated to another host in the cluster. Update a host when its usage is relatively low.
  • In a self-hosted engine environment, the Manager virtual machine can only migrate between self-hosted engine nodes in the same cluster. It cannot migrate to standard hosts.
  • The cluster must have sufficient memory reserved for its hosts to perform maintenance. Otherwise, virtual machine migrations will hang and fail. You can reduce the memory usage of host updates by shutting down some or all virtual machines before updating hosts.
  • Do not update all hosts at the same time, as one host must remain available to perform Storage Pool Manager (SPM) tasks.
  • You cannot migrate a pinned virtual machine (such as a virtual machine using a vGPU) to another host. Pinned virtual machines must be shut down before updating the host.

Procedure

  1. Ensure the correct repositories are enabled. You can check which repositories are currently enabled by running yum repolist.

    • For Red Hat Virtualization Hosts:

      # subscription-manager repos --enable=rhel-7-server-rhvh-4-rpms
    • For Red Hat Enterprise Linux hosts:

      # subscription-manager repos \
          --enable=rhel-7-server-rpms \
          --enable=rhel-7-server-rhv-4-mgmt-agent-rpms \
          --enable=rhel-7-server-ansible-2-rpms
  2. In the Administration Portal, click ComputeHosts and select the host to be updated.
  3. Click ManagementMaintenance.
  4. Update the host:

    # yum update
  5. Reboot the host to ensure all updates are correctly applied.

    Note

    Check the imgbased logs to see if any additional package updates have failed for a Red Hat Virtualization Host. If some packages were not successfully reinstalled after the update, check that the packages are listed in /var/imgbased/persisted-rpms. Add any missing packages then run rpm -Uvh /var/imgbased/persisted-rpms/*.

Repeat this process for each host in the Red Hat Virtualization environment.