sporadic packet loss with Windows 2008R2 guests

[jdickson]

Hello there..

I'm experiencing some troubling networking dropouts with my Server 2008R2 guests. Linux guests do not seem to be affected, and connectivity to the host seems solid.

My host has four gigabit interfaces bonded together, three of which are currently active. LACP status looks good on the switch, which is an HP2910AL. No errors indicated on any of the switchports. I'm using tagging specified on the guest NIC hardware to place the VMs in the proper VLANs.

If I start a ping to my Server 2008R2 guests, after a few minutes I'll get a packet dropout (using regular windows ping, so just one ping per second). If I'm also running a ping out to another host from the guest in question, at the same time I'll generally get a packet dropout there as well.

I've tried using both virtio networking and the e1000 driver, and have the same results. I'm also seeing this across two different pieces of hardware.. both Dell, but wildly different generations of Dell..

I'm running Prox v 3.0-20/0428106c

Does this ring a bell with anyone?

Thanks,

Joe

 

[jdickson]

I'm experiencing some troubling networking dropouts with my Server 2008R2 guests. Linux guests do not seem to be affected, and connectivity to the host seems solid.

I seem to have found the culprit.. I did some tcpdump diagnostics, and noticed that right before the packet timeouts the VM guest sent an IGMP v2 report. I blocked IGMP packets at the switch level, and that seems to have resolved the issues with my Server 2008R2 guests that had the packet timeouts.

Unsure why the IGMP report was causing packet drops, but for now I'll take it Anyone heard of this issue before?

Thanks,

Joe