Wednesday, August 11, 2010

VMware Management Assistant Panics on Magny Cours

VMware's current version of its vSphere Management Assistant - also known as vMA (pronounced "vee mah") - will crash when run on an ESX host using AMD Magny Cours processors. This behavior was discovered recently when installing the vMA on an AMD Opteron 6100 system (aka. Magny Cours) causing a "kernel panic" on boot after deploying the OVF template. Something of note is the crash also results in 100% vCPU utilization until the VM is either powered-off or reset:

[caption id="attachment_1624" align="aligncenter" width="436" caption="vMA Kernel Panic on Import"]vMA Kernel Panic on Import[/caption]

As it turns out, no manner of tweaks to the virtual machine's virtualization settings nor OS boot/grub settings (i.e. noapic, etc.) seem to cure the ills for vMA. However, we did discover that the OVF deployed appliance was configured as a VMware Virtual Machine Hardware Version 4 machine:

[caption id="attachment_1625" align="aligncenter" width="450" caption="vMA 4.1 defaults to Virtual Machine Hardware Version 4"]vMA 4.1 defaults to Hardware Version 4[/caption]

Since our lab vMA deployments have all been upgraded to Virtual Machine Harware Version 7 for some time (and for functional benefits as well), we tried to update the vMA to Version 7 and try again:

[caption id="attachment_1626" align="aligncenter" width="450" caption="Upgrade vMA Virtual Machine Version..."]Upgrade vMA Virtual Machine Version...[/caption]

This time, with Virtual Hardware Version 7 (and no other changes to the VM), the vMA boots as it should:

[caption id="attachment_1627" align="aligncenter" width="450" caption="vMA Booting after Upgrade to Virtual Hardware Version 7"]vMA Booting after Upgrade to Virtual Hardware Version 7[/caption]

Since the Magny Cours CPU is essentially a pair of tweaked 6-core Opteron CPUs in a single package, we took the vMA into the lab and deployed it to an ESX server running on AMD 2435 6-core CPUs: the vMA booted as expected, even with Virtual Hardware Version 4. A quick check of the community and support boards show a few issues with older RedHat/Centos kernels (like vMA's) but no reports of kernel panic with Magny Cours. Perhaps there are just not that many AMD Opteron 6100 deployments out there with vMA yet...