Comment 20 for bug 1180419

Confirmed in all raring installations running under both hyper-v server 2008 R2 as well as hyper-v server 2012 with 30+ of virtual machines.
Unfortunately I've upgraded all of my Ubuntu 12.10 virtual machines.

The problem exists not only when shutting down guest operating system manually but also in case the Hypervisor wants to shut down the virtual machine (e.g. during hypervisor's restart or stopping due to UPS battery low signal).

In such situation virtual machine with Ubuntu crashes (and due to crash sd rejects I/O to offline device so e.g. MySQL replication or MySQL itself is usually broken) with no information to hypervisor and due this hypervisor's restart or shut down cannot be finished, what can also cause the crash the hypervisor's harddisks (e.g. when UPS battery gets exhausted).

I'm a little bit astonished why this bug is not solved yet and even not assigned to anyone, as it DISABLES IN TOTAL the possibility of USING Ubuntu 13.04 IN PRODUCTION environment basing on Hyper-V virtualization.

In my opinion it shouldn't be categorized as medium importance as it is the CRITICAL one.