How to change the reboot setting so linux machines reboot immediately after patching (using Azure Arc -Update Manager), and do not wait 10minutes before they reboot.

Question

I am setting up linux (RHEL) machines to be patched using Azure Arc (Update Manager) on a schedule. I have the option to reboot the machines after patching, so I selected that, but every time the patching is done, it waits 10mins before the machine is rebooted, and sends messages/warnings every minute to the users logged in on the time the machine will be rebooted.

How can I change the reboot setting in the Azure Arc/Update Manager schedule, so the machines reboot immediately after patching, and do not give a warning messages?

Thank you

Answer 1

Hi Yessica Deseck,

I Understand that your facing a issue with reboot after the update installation by azure update management.

Actually, based on the azure support limits the maintenance window controls the number of updates that can be installed on your virtual machine and Arc-enabled servers.

For example, if a maintenance window is of 3 hours and starts at 3:00 PM, the following are the details on how the updates are installed:

Linux

Update Type Details: -

Reboot If the VMs need a reboot, you need to have 15 minutes left in the maintenance window, else the reboot is skipped.

Note: This is only applicable for Azure VMs and not for Arc-enabled servers.

In this example, you must start the reboot by 5:45 PM.

https://learn.microsoft.com/en-us/azure/update-manager/scheduled-patching?tabs=schedule-updates-single-machine%2Cschedule-updates-scale-overview%2Clinux-maintenance#timeline-of-maintenance-window

Which means we need to configure the maintenance including the reboot time.

After the installation the machine take 15 to complete the reboot as your vms rebooting which is expected and recommend procedure.

Additionally, we have the options while scheduling the update manager

Reboot if required:

This is the most common and recommended approach. It ensures that updates requiring a reboot are handled without unnecessary restarts. For example, kernel upgrades or driver updates typically require a reboot to load the new version.

Again,

A reboot can occur even if you specify Never Reboot in the Schedule settings. Configure these registry keys to best suit your environment

https://learn.microsoft.com/en-us/azure/update-manager/scheduled-patching?tabs=schedule-updates-single-machine%2Cschedule-updates-scale-overview%2Cwindows-maintenance#configure-reboot-settings

Never reboot:

This option is useful for updates that can be applied without interrupting the running system. For example, memory-preserving updates on Azure VMs can be applied without a reboot, as the VM is paused while the updates are applied. Similarly, some database updates can be performed with minimal downtime by creating a temporary instance and replicating data.

Always reboot:

While this approach guarantees that all updates are fully applied, it can lead to unnecessary downtime. It's generally not recommended unless there's a specific need to ensure all updates are fully applied before proceeding, such as with certain system-level updates.

So, as per the public documents and support limits the recommended procedure is to configure the maintenance including reboot time to avoid the use usage problems.

Hope the above provided information help you resolve the issue, if you have any further concerns or queries, please feel free to reach out to us.

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