Azure Guest OS supportability and retirement policy
The information on this page relates to the Azure Guest operating system (Guest OS) for Cloud Services worker and web roles (PaaS). It does not apply to Virtual Machines (IaaS).
Microsoft has a published support policy for the Guest OS. The page you are reading now describes how the policy is implemented.
The policy is
- Microsoft will support at least the latest two families of the Guest OS. When a family is retired, customers have 12 months from the official retirement date to update to a newer supported Guest OS family.
- Microsoft will support at least the latest two versions of the supported Guest OS families.
- Microsoft will support at least the latest two versions of the Azure SDK. When a version of the SDK is retired, customers will have 12 months from the official retirement date to update to a newer version.
At times, more than two families or releases may be supported. Official Guest OS support information will appear on the Azure Guest OS Releases and SDK Compatibility Matrix.
When a Guest OS version is retired
New Guest OS versions are introduced about every month to incorporate the latest MSRC updates. Because of the regular monthly updates, a Guest OS version is normally disabled around 60 days after its release. This activity keeps at least two Guest OS versions for each family available for use.
Process during a Guest OS family retirement
Once the retirement is announced, customers have a 12 month "transition" period before the older family is officially removed from service. This transition time may be extended at the discretion of Microsoft. Updates will be posted on the Azure Guest OS Releases and SDK Compatibility Matrix.
A gradual retirement process will begin six (6) months into the transition period. During this time:
- Microsoft will notify customers of the retirement.
- The newer version of the Azure SDK won’t support the retired Guest OS family.
- New deployments and redeployments of Cloud Services will not be allowed on the retired family
Microsoft will continue to introduce new Guest OS version incorporating the latest MSRC updates until the last day of the transition period, known as the "expiration date". On the expiration date, Cloud Services still running will be unsupported under the Azure SLA. Microsoft has the discretion to force upgrade, delete or stop those services after that date.
Process during a Guest OS Version retirement
If customers set their Guest OS to automatically update, they never have to worry about dealing with Guest OS versions. They will always be using the latest Guest OS version.
Guest OS Versions are released every month. Because of the rate of regular releases, each version has a fixed lifespan.
At 60 days into the lifespan, a version is "disabled". "Disabled" means that the version is removed from the portal. The version can no longer be set from the CSCFG configuration file. Existing deployments are left running. But new deployments and code and configuration updates to existing deployments will not be allowed.
Sometime after becoming "disabled", the Guest OS version "expires" and any installations still running that expired version are exposed to security and vulnerability issues. Generally, expiration is done in batches, so the period from disablement to expiration can vary.
Customers who configure their services to update the Guest OS manually, should ensure that their services are running on a supported Guest OS. If a service is configured to update the Guest OS automatically, the underlying platform will ensure compliance and will upgrade to the latest Guest OS.
These periods may be made longer at Microsoft's discretion to ease customer transitions. Any changes will be communicated on the Azure Guest OS Releases and SDK Compatibility Matrix.
Notifications during retirement
- Family retirement
Microsoft will use blog posts and portal notification. Customers who are still using a retired Guest OS family will be notified through direct communication (email, portal messages, phone call) to assigned service administrators. All changes will be posted to the Azure Guest OS Releases and SDK Compatibility Matrix.
- Version Retirement
All changes and the dates they occur will be posted to the Azure Guest OS Releases and SDK Compatibility Matrix, including release, disabled, and expiration. Services admins will receive emails if they have deployments running on a disabled Guest OS version or family. The timing of these emails can vary. Generally they are at least a month before disablement, though this timing is not an official SLA.
Frequently asked questions
How can I mitigate the impacts of migration?
We recommend that you use latest Guest OS family for designing your Cloud Services.
- Start planning your migration to a newer family early.
- Set up temporary test deployments to test your Cloud Service running on the new family.
- Set your Guest OS version to Automatic (osVersion=* in the .cscfg file) so the migration to new Guest OS versions occurs automatically.
What if my web application requires deeper integration with the OS?
If your web application architecture depends on underlying features of the operating system, use platform supported capabilities such as startup tasks or other extensibility mechanisms. Alternatively, you can also use Azure Virtual Machines (IaaS – Infrastructure as a Service), where you are responsible for maintaining the underlying operating system.
Review the latest Guest OS releases.