Upgrading from RHEL 7 to RHEL 8

Overview

This article provides step-by-step instructions to upgrade the existing NSX Advanced Load Balancer (previously Avi) - LSC deployments from RHEL 7 to RHEL 8.

Prerequisites

Ensure the following pre-requisites are met before initiating the upgrade:

The Avi Controller/ SE hosts which are being upgraded from RHEL 7.9 to 8.x are of version 21.1.3 or higher.
Docker is in running state until the Avi image is successfully loaded in Podman. It is recommended to not purge or uninstall docker until then.
Extra disk space is required for the Avi Controller (24G)/ SE (12G) images to be successfully loaded in Podman from Docker.

Note: Rollback from NSX Advanced Load Balancer version 21.1.3 is not allowed after upgrade to RHEL 8.x host.

Upgrading the Existing Avi - LSC Deployments to RHEL 8

To upgrade the Avi-LSC deployments from RHEL 7 to RHEL 8,

Stop and disable the Avi Controller/ Avi SE on the host(s) that are being upgraded:

On Controller Hosts


 systemctl stop avicontroller
 systemctl disable avicontroller

On SE Hosts


 systemctl stop avise
 systemctl disable avise

Upgrade from RHEL 7 to RHEL 8 using the steps mentioned here.

Note: If you are not migrating the Docker Avi images to Podman, do not remove or purge Docker.
After booting in RHEL 8.x, install and upgrade Podman to 3.1.0.
Install the appropriate Kernel version for RHEL 8.x.

Install, enable and start network-scripts on the RHEL 8.x host:


 yum install network-scripts
 systemctl enable network
 systemctl start network

Reboot the host after enabling the Avi Controller / Avi SE:

On Controller Hosts
```
 systemctl enable avicontroller
 
```
On SE Hosts
```
 systemctl enable avise
 
```

NSX Advanced Load Balancer will come up with Podman.

Notes:

After upgrade to RHEL 8.x, the host boots up with a default RHEL 8.x kernel which might not be supported or qualified by NSX Advanced Load Balancer. In this case, downgrade the Kernel to a supported version.
For Avi upgrades from 21.1.3 to any future version, upload the relevant Avi image only after RHEL OS upgrade is done.