Support Policies for RHEL High Availability Clusters - Microsoft Azure Virtual Machines as Cluster Members

Contents

• Overview
  • Applicable Environments
  • Recommended Prior Reading
  • Useful References and Guides
  • Introduction
• Policies

Overview

Applicable Environments

• Red Hat Enterprise Linux (RHEL) with the High Availability Add-On
• Using Microsoft Azure to provide instances that may serve as High Availability cluster members

Recommended Prior Reading

• General conditions with virtualized cluster members

Useful References and Guides

• Support Policies for RHEL High Availability Clusters
• Support Policies for RHEL High Availability clusters - fence_azure_arm
• Administrative Procedures - Installing and configuring a Red Hat Enterprise Linux 7.4 (and later)High Availability cluster on Microsoft Azure

Introduction

This guide offers Red Hat's policies, requirements, and limitations applicable to the use of Microsoft Azure virtual machines as members of a RHEL High Availability cluster. Users of RHEL High Availability software components should adhere to these policies by installing only on the approved platforms in order to be eligible to receive assistance from Red Hat Support with the appropriate support subscriptions.

Policies

Consider general conditions for support of RHEL High Availability in virtualization environments

• See: General conditions with virtualized cluster members

Supported releases for Microsoft Azure virtual machines as High Availability members: Red Hat supports RHEL High Availability cluster members running on Microsoft Azure virtual machines with the following RHEL releases or later:

• RHEL 8: Supported by Red Hat
• RHEL 7:
  • RHEL 7.6 or later: Supported by Red Hat with packages pacemaker-1.1.19-8.el7, corosync-2.4.3-4.el7, fence-agents-4.2.1-11.el7_6.8 or later.
  • RHEL 7.5 or later: Supported by Red Hat with packages pacemaker-1.1.18-11.el7, corosync-2.4.3-2.el7, fence-agents-4.0.11-86.el7_5.8 or later.
  • RHEL 7.4: Supported by Red Hat with packages pacemaker-1.1.16-12.el7_4.8, corosync-2.4.0-9.el7_4.2, fence-agents-4.0.11-66.el7_4.12 or later.

Supported releases for Microsoft Azure virtual machines as High Availability members using managed identity (MSI): Red Hat supports RHEL High Availability cluster members running on Microsoft Azure virtual machines using managed identity authentication (MSI) with the following RHEL releases or later:

• RHEL 9: Supported by Red Hat.
• RHEL 8:
  • RHEL 8.4 or later: Supported by Red Hat.
  • RHEL 8.2: Supported by Red Hat with packages fence-agents-4.2.1-41.el8_2.4 or later.
• RHEL 7:
  • RHEL 7.9: Supported by Red Hat with packages fence-agents-4.2.1-41.el7_9.4 or later.

Supported transport protocols: RHEL 7 High Availability clusters with members that run on the Microsoft Azure platform can only use the udpu transport protocol - which is the default in RHEL 7 clusters. Azure VNETs do not support multicast traffic, preventing the usage of the udp transport protocol.

Red Hat supports only the knet transport protocol on RHEL 8, regardless of platform.

For more information, see:

• Support policies - Transport protocols
• docs.microsoft.com - Azure Virtual Network FAQ
• Explore features - Overview of transport protocols
• Design guidance - Selecting the transport protocol
• Design Guidance for RHEL High Availability Clusters - Microsoft Azure Virtual Machines as Cluster Members
• Installing and Configuring a Red Hat Enterprise Linux 7.4 (and later) High-Availability Cluster on Microsoft Azure

Supported releases for Microsoft Azure Government VMs as High Availability: Red Hat supports RHEL High Availability cluster members running on Microsoft Azure Government VMs with the following RHEL releases or later:

• RHEL 9: Supported by Red Hat.
• RHEL 8.4 or later: Supported by Red Hat.

When using a government cloud you must specify the cloud option when configuring your fence agent. For example, cloud=usgov for the US government cloud. Other options available at this time are germany and china.

No support for Azure Stack Hub VMs as RHEL High Availability cluster members: Red Hat does not support RHEL High Availability deployments consisting of members that are virtual machines running on the Azure Stack Hub on-premises cloud platform.

• RHEL 7: Not supported.
• RHEL 8: Not supported. For more information see: RHEL-7626.
• RHEL 9: Not supported. For more information see: Bugzilla bug 2211930

One of the reasons why that Azure Stack Hub VMs are not supported is due to inability to support floating IPs on Azure Stack Hub.

No support for Azure Stack HCI VMs as RHEL High Availability cluster members: Red Hat does not support RHEL High Availability deployments consisting of members that are virtual machines running on the Azure Stack HCI on-premises cloud platform.

Cluster nodes hosted on VMware Cloud hosts on AVS (Azure Vmware Solutions): Currently this is unsupported and for more information see: Does Red Hat support VMware Cloud hosts on AVS (Azure Vmware Solutions) as members of a RHEL High Availability cluster?