We have recently upgraded from xen 3.4.4 to xen 4.1.2 and when completing this upgrade it appears the systems rebooted into the kernel for xen 3.4.4 vs the proper kernel for 4.1.2. We have identified the root cause and rebooted the nodes into the proper kernel that should resolve the issues of instability this has caused. We had upgraded to xen 4.1.2 in the first place to correct issues with IPv6 in Xen 3.4.4