Chapter 4. Updates between minor releases


4.1. Updating Red Hat Virtualization between minor releases

To update from your current version of 4.4 to the latest version of 4.4, update the Manager, update the hosts, and then change the compatibility version for the cluster, virtual machines, and data center.

Note

If upgrading from version 4.4.9 to a later version fails on RHVH, run the dnf reinstall redhat-virtualization-host-image-update command to fix the issue.

Upgrade Considerations

  • When planning to upgrade, see Red Hat Virtualization 4.4 upgrade considerations and known issues.
  • When upgrading from Open Virtual Network (OVN) and Open vSwitch (OvS) 2.11 to OVN 2021 and OvS 2.15, the process is transparent to the user as long as the following conditions are met:

    • The Manager is upgraded first.
    • The ovirt-provider-ovn security groups must be disabled, before the host upgrade, for all OVN networks that are expected to work between hosts with OVN/OvS version 2.11.
    • The hosts are upgraded to match OVN version 2021 or higher and OvS version 2.15. You must complete this step in the Administration Portal, so you can properly reconfigure OVN and refresh the certificates.
    • The host is rebooted after an upgrade.
Note

To verify whether the provider and OVN were configured successfully on the host, check the OVN configured flag on the General tab for the host. If the OVN Configured is set to No, click Management Refresh Capabilities. This setting is also available in the REST API. If refreshing the capabilities fails, you can configure OVN by reinstalling the host from Manager 4.4 or higher.

4.1.1. Analyzing the Environment

It is recommended to run the Log Collection Analysis tool and the Image Discrepancies tool prior to performing updates and for troubleshooting. These tools analyze your environment for known issues that might prevent you from performing an update, and provide recommendations to resolve them.

4.1.2. Log Collection Analysis tool

Run the Log Collection Analysis tool prior to performing updates and for troubleshooting. The tool analyzes your environment for known issues that might prevent you from performing an update, and provides recommendations to resolve them. The tool gathers detailed information about your system and presents it as an HTML file.

Prerequisites

  • Ensure the Manager has the correct repositories enabled. For the list of required repositories, see Enabling the Red Hat Virtualization Manager Repositories for Red Hat Virtualization 4.4.

    Updates to the Red Hat Virtualization Manager are released through the Content Delivery Network.

Procedure

  1. Install the Log Collection Analysis tool on the Manager machine:

    # yum install rhv-log-collector-analyzer
  2. Run the tool:

    # rhv-log-collector-analyzer --live

    A detailed report is displayed.

    By default, the report is saved to a file called analyzer_report.html.

    To save the file to a specific location, use the --html flag and specify the location:

    # rhv-log-collector-analyzer --live --html=/directory/filename.html
  3. You can use the ELinks text mode web browser to read the analyzer reports within the terminal. To install the ELinks browser:

    # yum install -y elinks
  4. Launch ELinks and open analyzer_report.html.

    # elinks /home/user1/analyzer_report.html

    To navigate the report, use the following commands in ELinks:

    • Insert to scroll up
    • Delete to scroll down
    • PageUp to page up
    • PageDown to page down
    • Left Bracket to scroll left
    • Right Bracket to scroll right

4.1.2.1. Monitoring snapshot health with the image discrepancies tool

The RHV Image Discrepancies tool analyzes image data in the Storage Domain and RHV Database. It alerts you if it finds discrepancies in volumes and volume attributes, but does not fix those discrepancies. Use this tool in a variety of scenarios, such as:

  • Before upgrading versions, to avoid carrying over broken volumes or chains to the new version.
  • Following a failed storage operation, to detect volumes or attributes in a bad state.
  • After restoring the RHV database or storage from backup.
  • Periodically, to detect potential problems before they worsen.
  • To analyze a snapshot- or live storage migration-related issues, and to verify system health after fixing these types of problems.

Prerequisites

  • Required Versions: this tool was introduced in RHV version 4.3.8 with rhv-log-collector-analyzer-0.2.15-0.el7ev.
  • Because data collection runs simultaneously at different places and is not atomic, stop all activity in the environment that can modify the storage domains. That is, do not create or remove snapshots, edit, move, create, or remove disks. Otherwise, false detection of inconsistencies may occur. Virtual Machines can remain running normally during the process.

Procedure

  1. To run the tool, enter the following command on the RHV Manager:

    # rhv-image-discrepancies
  2. If the tool finds discrepancies, rerun it to confirm the results, especially if there is a chance some operations were performed while the tool was running.
Note

This tool includes any Export and ISO storage domains and may report discrepancies for them. If so, these can be ignored, as these storage domains do not have entries for images in the RHV database.

Understanding the results

The tool reports the following:

  • If there are volumes that appear on the storage but are not in the database, or appear in the database but are not on the storage.
  • If some volume attributes differ between the storage and the database.

Sample output:

 Checking storage domain c277ad93-0973-43d9-a0ca-22199bc8e801
    Looking for missing images...
    No missing images found
    Checking discrepancies between SD/DB attributes...
    image ef325650-4b39-43cf-9e00-62b9f7659020 has a different attribute capacity on storage(2696984576) and on DB(2696986624)
    image 852613ce-79ee-4adc-a56a-ea650dcb4cfa has a different attribute capacity on storage(5424252928) and on DB(5424254976)

 Checking storage domain c64637b4-f0e8-408c-b8af-6a52946113e2
    Looking for missing images...
    No missing images found
    Checking discrepancies between SD/DB attributes...
    No discrepancies found

To update a standalone Manager, follow the standard procedure for minor updates:

4.1.3. Updating the Red Hat Virtualization Manager

Prerequisites

  • Ensure the Manager has the correct repositories enabled. For the list of required repositories, see Enabling the Red Hat Virtualization Manager Repositories for Red Hat Virtualization 4.4.

    Note

    If you are upgrading from RHV version 4.4.0 through 4.4.8 to RHV version 4.4.9 or later, you must add the EAP 7.4 channel to the list of subscription repositories jb-eap-7.4-for-rhel-8-x86_64-rpms, and following the upgrade, remove the jb-eap-7.3-for-rhel-8-x86_64-rpms from the lisat of subscription repositories.

    Updates to the Red Hat Virtualization Manager are released through the Content Delivery Network.

Procedure

  1. On the Manager machine, check if updated packages are available:

    # engine-upgrade-check
  2. Update the setup packages:

    # yum update ovirt\*setup\* rh\*vm-setup-plugins
  3. Update the Red Hat Virtualization Manager with the engine-setup script. The engine-setup script prompts you with some configuration questions, then stops the ovirt-engine service, downloads and installs the updated packages, backs up and updates the database, performs post-installation configuration, and starts the ovirt-engine service.

    # engine-setup

    When the script completes successfully, the following message appears:

    Execution of setup completed successfully
    Note

    The engine-setup script is also used during the Red Hat Virtualization Manager installation process, and it stores the configuration values supplied. During an update, the stored values are displayed when previewing the configuration, and might not be up to date if engine-config was used to update configuration after installation. For example, if engine-config was used to update SANWipeAfterDelete to true after installation, engine-setup will output "Default SAN wipe after delete: False" in the configuration preview. However, the updated values will not be overwritten by engine-setup.

    Important

    The update process might take some time. Do not stop the process before it completes.

  4. Update the base operating system and any optional packages installed on the Manager:

    # yum update --nobest
    Important

    If you encounter a required Ansible package conflict during the update, see Cannot perform yum update on my RHV manager (ansible conflict).

    Important

    If any kernel packages were updated, reboot the machine to complete the update.

4.1.4. Updating a Self-Hosted Engine

To update a self-hosted engine from your current version to the latest version, you must place the environment in global maintenance mode and then follow the standard procedure for updating between minor versions.

Note

Ensure the Manager has the correct repositories enabled. For the list of required repositories, see the section Updating the Red Hat Virtualization Manager.

Enabling global maintenance mode

You must place the self-hosted engine environment in global maintenance mode before performing any setup or upgrade tasks on the Manager virtual machine.

Procedure

  1. Log in to one of the self-hosted engine nodes and enable global maintenance mode:

    # hosted-engine --set-maintenance --mode=global
  2. Confirm that the environment is in global maintenance mode before proceeding:

    # hosted-engine --vm-status

    You should see a message indicating that the cluster is in global maintenance mode.

Updating the Red Hat Virtualization Manager

Prerequisites

  • Ensure the Manager has the correct repositories enabled. For the list of required repositories, see Enabling the Red Hat Virtualization Manager Repositories for Red Hat Virtualization 4.4.

    Note

    If you are upgrading from RHV version 4.4.0 through 4.4.8 to RHV version 4.4.9 or later, you must add the EAP 7.4 channel to the list of subscription repositories jb-eap-7.4-for-rhel-8-x86_64-rpms, and following the upgrade, remove the jb-eap-7.3-for-rhel-8-x86_64-rpms from the lisat of subscription repositories.

    Updates to the Red Hat Virtualization Manager are released through the Content Delivery Network.

Procedure

  1. On the Manager machine, check if updated packages are available:

    # engine-upgrade-check
  2. Update the setup packages:

    # yum update ovirt\*setup\* rh\*vm-setup-plugins
  3. Update the Red Hat Virtualization Manager with the engine-setup script. The engine-setup script prompts you with some configuration questions, then stops the ovirt-engine service, downloads and installs the updated packages, backs up and updates the database, performs post-installation configuration, and starts the ovirt-engine service.

    # engine-setup

    When the script completes successfully, the following message appears:

    Execution of setup completed successfully
    Note

    The engine-setup script is also used during the Red Hat Virtualization Manager installation process, and it stores the configuration values supplied. During an update, the stored values are displayed when previewing the configuration, and might not be up to date if engine-config was used to update configuration after installation. For example, if engine-config was used to update SANWipeAfterDelete to true after installation, engine-setup will output "Default SAN wipe after delete: False" in the configuration preview. However, the updated values will not be overwritten by engine-setup.

    Important

    The update process might take some time. Do not stop the process before it completes.

  4. Update the base operating system and any optional packages installed on the Manager:

    # yum update --nobest
    Important

    If you encounter a required Ansible package conflict during the update, see Cannot perform yum update on my RHV manager (ansible conflict).

    Important

    If any kernel packages were updated:

    1. Disable global maintenance mode
    2. Reboot the machine to complete the update.
Disabling global maintenance mode

Procedure

  1. Log in to the Manager virtual machine and shut it down.
  2. Log in to one of the self-hosted engine nodes and disable global maintenance mode:

    # hosted-engine --set-maintenance --mode=none

    When you exit global maintenance mode, ovirt-ha-agent starts the Manager virtual machine, and then the Manager automatically starts. It can take up to ten minutes for the Manager to start.

  3. Confirm that the environment is running:

    # hosted-engine --vm-status

    The listed information includes Engine Status. The value for Engine status should be:

    {"health": "good", "vm": "up", "detail": "Up"}
    Note

    When the virtual machine is still booting and the Manager hasn’t started yet, the Engine status is:

    {"reason": "bad vm status", "health": "bad", "vm": "up", "detail": "Powering up"}

    If this happens, wait a few minutes and try again.

4.1.5. Updating All Hosts in a Cluster

You can update all hosts in a cluster instead of updating hosts individually. This is particularly useful during upgrades to new versions of Red Hat Virtualization. See oVirt Cluster Upgrade for more information about the Ansible role used to automate the updates.

Update one cluster at a time.

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 the cluster has migration enabled, virtual machines are automatically migrated to another host in the cluster.
  • 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.
  • You cannot migrate a pinned virtual machine (such as a virtual machine using a vGPU) to another host. Pinned virtual machines are shut down during the update, unless you choose to skip that host instead.

Procedure

  1. In the Administration Portal, click Compute Clusters and select the cluster. The Upgrade status column shows if an upgrade is available for any hosts in the cluster.
  2. Click Upgrade.
  3. Select the hosts to update, then click Next.
  4. Configure the options:

    • Stop Pinned VMs shuts down any virtual machines that are pinned to hosts in the cluster, and is selected by default. You can clear this check box to skip updating those hosts so that the pinned virtual machines stay running, such as when a pinned virtual machine is running important services or processes and you do not want it to shut down at an unknown time during the update.
    • Upgrade Timeout (Minutes) sets the time to wait for an individual host to be updated before the cluster upgrade fails with a timeout. The default is 60. You can increase it for large clusters where 60 minutes might not be enough, or reduce it for small clusters where the hosts update quickly.
    • Check Upgrade checks each host for available updates before running the upgrade process. It is not selected by default, but you can select it if you need to ensure that recent updates are included, such as when you have configured the Manager to check for host updates less frequently than the default.
    • Reboot After Upgrade reboots each host after it is updated, and is selected by default. You can clear this check box to speed up the process if you are sure that there are no pending updates that require a host reboot.
    • Use Maintenance Policy sets the cluster’s scheduling policy to cluster_maintenance during the update. It is selected by default, so activity is limited and virtual machines cannot start unless they are highly available. You can clear this check box if you have a custom scheduling policy that you want to keep using during the update, but this could have unknown consequences. Ensure your custom policy is compatible with cluster upgrade activity before disabling this option.
  5. Click Next.
  6. Review the summary of the hosts and virtual machines that are affected.
  7. Click Upgrade.
  8. A cluster upgrade status screen displays with a progress bar showing the precentage of completion, and a list of steps in the upgrade process that have completed. You can click Go to Event Log to open the log entries for the upgrade. Closing this screen does not interrupt the upgrade process.

You can track the progress of host updates:

  • in the Compute Clusters view, the Upgrade Status column displays a progress bar that displays the percentage of completion.
  • in the Compute Hosts view
  • in the Events section of the Notification Drawer ( EventsIcon ).

You can track the progress of individual virtual machine migrations in the Status column of the Compute Virtual Machines view. In large environments, you may need to filter the results to show a particular group of virtual machines.

You can now update the cluster compatibility version.

4.1.6. Changing the Cluster Compatibility Version

Red Hat Virtualization clusters have a compatibility version. The cluster compatibility version indicates the features of Red Hat Virtualization supported by all of the hosts in the cluster. The cluster compatibility is set according to the version of the least capable host operating system in the cluster.

Prerequisites

  • To change the cluster compatibility level, you must first update all the hosts in your cluster to a level that supports your desired compatibility level. Check if there is an icon next to the host indicating an update is available.

Limitations

  • Virtio NICs are enumerated as a different device after upgrading the cluster compatibility level to 4.6. Therefore, the NICs might need to be reconfigured. Red Hat recommends that you test the virtual machines before you upgrade the cluster by setting the cluster compatibility level to 4.6 on the virtual machine and verifying the network connection.

    If the network connection for the virtual machine fails, configure the virtual machine with a custom emulated machine that matches the current emulated machine, for example pc-q35-rhel8.3.0 for 4.5 compatibility version, before upgrading the cluster.

Procedure

  1. In the Administration Portal, click Compute Clusters.
  2. Select the cluster to change and click Edit.
  3. On the General tab, change the Compatibility Version to the desired value.
  4. Click OK. The Change Cluster Compatibility Version confirmation dialog opens.
  5. Click OK to confirm.
Important

An error message might warn that some virtual machines and templates are incorrectly configured. To fix this error, edit each virtual machine manually. The Edit Virtual Machine window provides additional validations and warnings that show what to correct. Sometimes the issue is automatically corrected and the virtual machine’s configuration just needs to be saved again. After editing each virtual machine, you will be able to change the cluster compatibility version.

You can now update the cluster compatibility version for virtual machines in the cluster.

4.1.7. Changing Virtual Machine Cluster Compatibility

After updating a cluster’s compatibility version, you must update the cluster compatibility version of all running or suspended virtual machines by rebooting them from the Administration Portal, or using the REST API, or from within the guest operating system. Virtual machines that require a reboot are marked with the pending changes icon ( pendingchanges ).

Although you can wait to reboot the virtual machines at a convenient time, rebooting immediately is highly recommended so that the virtual machines use the latest configuration. Any virtual machine that has not been rebooted runs with the previous configuration, and subsequent configuration changes made to the virtual machine might overwrite its pending cluster compatibility changes.

Procedure

  1. In the Administration Portal, click Compute Virtual Machines.
  2. Check which virtual machines require a reboot. In the Vms: search bar, enter the following query:

    next_run_config_exists=True

    The search results show all virtual machines with pending changes.

  3. Select each virtual machine and click Restart. Alternatively, if necessary you can reboot a virtual machine from within the virtual machine itself.

When the virtual machine starts, the new compatibility version is automatically applied.

Note

You cannot change the cluster compatibility version of a virtual machine snapshot that is in preview. You must first commit or undo the preview.

You can now update the data center compatibility version.

4.1.8. Changing the Data Center Compatibility Version

Red Hat Virtualization data centers have a compatibility version. The compatibility version indicates the version of Red Hat Virtualization with which the data center is intended to be compatible. All clusters in the data center must support the desired compatibility level.

Prerequisites

  • To change the data center compatibility level, you must first update the compatibility version of all clusters and virtual machines in the data center.

Procedure

  1. In the Administration Portal, click Compute Data Centers.
  2. Select the data center to change and click Edit.
  3. Change the Compatibility Version to the desired value.
  4. Click OK. The Change Data Center Compatibility Version confirmation dialog opens.
  5. Click OK to confirm.

You can also update hosts individually:

4.1.9. Updating Individual Hosts

Use the host upgrade manager to update individual hosts directly from the Administration Portal.

Note

The upgrade manager only checks hosts with a status of Up or Non-operational, but not Maintenance.

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 the cluster has migration enabled, 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.
  • 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 that the correct repositories are enabled. To view a list of currently enabled repositories, run dnf repolist.

    • For Red Hat Virtualization Hosts:

      # subscription-manager repos --enable=rhvh-4-for-rhel-8-x86_64-rpms
    • For Red Hat Enterprise Linux hosts:

      # subscription-manager repos \
          --enable=rhel-8-for-x86_64-baseos-eus-rpms \
          --enable=rhel-8-for-x86_64-appstream-eus-rpms \
          --enable=rhv-4-mgmt-agent-for-rhel-8-x86_64-rpms \
          --enable=advanced-virt-for-rhel-8-x86_64-rpms \
          --enable=fast-datapath-for-rhel-8-x86_64-rpms
      
      # subscription-manager release --set=8.6
  2. In the Administration Portal, click Compute Hosts and select the host to be updated.
  3. Click Installation Check for Upgrade and click OK.

    Open the Notification Drawer ( EventsIcon ) and expand the Events section to see the result.

  4. If an update is available, click Installation Upgrade.
  5. Click OK to update the host. Running virtual machines are migrated according to their migration policy. If migration is disabled for any virtual machines, you are prompted to shut them down.

    The details of the host are updated in Compute Hosts and the status transitions through these stages:

    Maintenance > Installing > Reboot > Up

    Note

    If the update fails, the host’s status changes to Install Failed. From Install Failed you can click Installation Upgrade again.

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

Note

You should update the hosts from the Administration Portal. However, you can update the hosts using dnf upgrade instead.

4.1.10. Manually Updating Hosts

Caution

This information is provided for advanced system administrators who need to update hosts manually, but Red Hat does not support this method. The procedure described in this topic does not include important steps, including certificate renewal, assuming advanced knowledge of such information. Red Hat supports updating hosts using the Administration Portal. For details, see Updating individual hosts or Updating all hosts in a cluster in the Administration Guide.

You can use the dnf 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 the cluster has migration enabled, 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.
  • 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 dnf repolist.

    • For Red Hat Virtualization Hosts:

      # subscription-manager repos --enable=rhvh-4-for-rhel-8-x86_64-rpms
    • For Red Hat Enterprise Linux hosts:

      # subscription-manager repos \
          --enable=rhel-8-for-x86_64-baseos-eus-rpms \
          --enable=rhel-8-for-x86_64-appstream-eus-rpms \
          --enable=rhv-4-mgmt-agent-for-rhel-8-x86_64-rpms \
          --enable=advanced-virt-for-rhel-8-x86_64-rpms \
          --enable=fast-datapath-for-rhel-8-x86_64-rpms
      
      # subscription-manager release --set=8.6
  2. In the Administration Portal, click Compute Hosts and select the host to be updated.
  3. Click Management Maintenance and OK.
  4. For Red Hat Enterprise Linux hosts:

    1. Identify the current version of Red Hat Enterprise Linux:

      # cat /etc/redhat-release
    2. Check which version of the redhat-release package is available:

      # dnf --refresh info --available redhat-release

      This command shows any available updates. For example, when upgrading from Red Hat Enterprise Linux 8.2.z to 8.3, compare the version of the package with the currently installed version:

      Available Packages
      Name         : redhat-release
      Version      : 8.3
      Release      : 1.0.el8
      …​
      Caution

      The Red Hat Enterprise Linux Advanced Virtualization module is usually released later than the Red Hat Enterprise Linux y-stream. If no new Advanced Virtualization module is available yet, or if there is an error enabling it, stop here and cancel the upgrade. Otherwise you risk corrupting the host.

    3. If the Advanced Virtualization stream is available for Red Hat Enterprise Linux 8.3 or later, reset the virt module:

      # dnf module reset virt
      Note

      If this module is already enabled in the Advanced Virtualization stream, this step is not necessary, but it has no negative impact.

      You can see the value of the stream by entering:

      # dnf module list virt
    4. Enable the virt module in the Advanced Virtualization stream with the following command:

      • For RHV 4.4.2:

        # dnf module enable virt:8.2
      • For RHV 4.4.3 to 4.4.5:

        # dnf module enable virt:8.3
      • For RHV 4.4.6 to 4.4.10:

        # dnf module enable virt:av
      • For RHV 4.4 and later:

        # dnf module enable virt:rhel
        Note

        Starting with RHEL 8.6 the Advanced virtualization packages will use the standard virt:rhel module. For RHEL 8.4 and 8.5, only one Advanced Virtualization stream is used, rhel:av.

  5. Enable version 14 of the nodejs module:

    # dnf module -y enable nodejs:14
  6. Update the host:

    # dnf upgrade --nobest
  7. 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.

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