If you’re hosted in Azure in the West US region you may be getting a free hardware upgrade later this month or early next month. Part of the Azure infrastructure is being upgraded and VMs that are running in the part which is being upgraded will be automatically to the new hardware.
Now if you’re going to be impacted whoever is your service administrator for your company will be getting (or has gotten) an email about this, which will include a reboot of all the impacted VMs. If your VMs are within an Availability Set then you’re guaranteed to only have one VM in the Availability Set reboot at a time. This is why we have Availability Sets.
In fact, this is all one of the reasons that Azure is a great platform. We’ve got systems that are getting moved to new, (hopefully) better hardware and there’s basically no impact to the systems in question. Just a rebooted of the impacted systems, that’s it. All in all, that’s a pretty minimal impact.
Now the email does include instructions if you’d like to schedule the upgrade yourself. Instead of letting Azure move your services automatically, just power down all the VMs in the Availability Set then power them back on. When they power back on they’ll be automatically moved to the new hardware. Yes this does mean that you have to take an outage but you’ve got two weeks notice to schedule the outage and complete it before Microsoft will force the issue.
All in all, that’s not bad.
If you’re getting the upgrade, enjoy that new server smell.