Q: (from Seth)
I’m working with a client on designing an Azure deployment for them and the question came up of how often are there scheduled maintenance windows in Azure and how can we decide who should get notifications about these maintenance windows.
Although we’d love for it to be perfect, it’s software and maintenance must happen. The goal is to minimize the impact to the customer. The use of Availability Sets is obviously one way the customer can mitigate the impact, Here is a great blog post on some details on our maintenance process and communication. Don’t let the title distract you, the concepts apply to all of our virtual machines:
To summarize key points:
- The maintenance that we are discussing applies to the underlying virtualization host environment of Azure, NOT the specific OS instances. Once an image has been created, the OS instance maintenance for patches and updates is up to you.
- We try to minimize the number of Azure maintenance cycles to minimize the customer impact. We’ve also have worked hard to make the maintenance cycle as quick as possible to minimize downtime.
- We target weekends if possible
- We try to provide seven days of notice, with three being the minimum for critical updates