Hyper-V telling fibs about Linux guest VMs
Ignore our 'overly aggressive' warnings, says Redmond, your VMs are healthy
If Microsoft's Hyper-V was found to treat Linux guests as second-class citizens, the resulting storm of controversy would probably generate enough heat and light to make a dent in some climate change models.
So there are probably a few brows being mopped down Redmond way this week over this knowledge base article titled “Degraded integration services message for non-Windows guests” explaining that while Hyper-V really is behaving in ways that make Linux guests look like second-class citizens, the software is telling fibs and all is well.
The article explains that “While running a non-Windows guest such as Linux on Hyper-V, the Hyper-V management console may display messages that indicate that the integration services for the non-Windows guest are degraded and no formal support will be provided unless the integration services are updated.”
Which sounds scary, until Microsoft explains that “This message is overtly aggressive in warning and users should feel free to ignore it. Microsoft will provide required support despite of these messages being shown in the Hyper-V console or the Windows event log.”
So why is Hyper-V doing this? Here's Microsoft's explanation:
“... non-Windows guest integration services may not always have the code to interoperate with the latest Hyper-V protocols. This is due to the fact that Windows release cycles are not in sync with the release cycles of other operating systems. As a hypothetical example, the latest Red Hat Enterprise Linux (RHEL) release may ship in January but the latest Windows release may ship in the following September. Between January and September, the Windows team may upgrade the Hyper-V protocols due to which the RHEL release shipped in January may have integration components that were written based on earlier Hyper-V protocols. Now, when a user tries to run an older RHEL release as a virtual machine on a newer Windows release then they may observe messages suggesting that the RHEL integration components are degraded.”
The article goes on to say that “... it is safe to ignore these messages because Hyper-V protocols are implemented to be backward compatible ...” and even if “... a certain non-Windows guest has integration services that were based off earlier Hyper-V protocols, the guest is expected to run flawlessly on newer Hyper-V releases.”
Panic over, then, for both Microsoft and the Linux community. But perhaps also a close-run thing, given the endless animus between fans of the two platforms. ®