We are using AOE devices for booting Xen virtual machines so that we can share a same physical device across different hosts using AOE.

It used to work well few days back. We did successful migrations. But lately booting a Xen domU from these AOE devices suddenly causes the system to crash. The system freezes, without any trace in logs. We have confirmed that this is not a Xen problem, as domUs booted from non-AOE devices work fine.

To reproduce same condition without Xen, I tried to do repetitive I/O on the AOE mounted device, to see if it crashes in the same way. But I couldn't make it crash the same way.

Could anyone suggest how we can debug this problem? Are there some tools (i figure tcpdump can't be used to see AOE traffic, is there any similar tool?), some logs? Some modifications in aoe module (debug mode etc.?)?

We greatly appreciate any help you can give.

Thanks very much.

Everything you can imagine is real