This week I implemented a couple of Dell 2950 Servers which contained an Intel quad-port nic. The physical switch ports were setup as a trunk so I used VST(Virtual Switch Tagging). I combined the onboard Broadcom ports with the Intel quad-port nics to have the most redundant setup. When I started testing the HA and DRS functionality I noticed that not everything worked like expected. After some basic troubleshooting it seemed that about half of the packets going via the Intel quad-port nics got dropped. A ping and vmkping confirmed this, the quad-port nic seemed to be broken. Today I discovered a topic about this problem on the VMTN forum. It seems I’m not the only one experiencing this weird problems, and it seems it’s not the quad-port nic that’s broken but the driver. Weird thing is that this is only with ports that are trunked. Access ports seem to work fine. According to user “inewby” VMware is working on a fix:
VMware Support have just got back to me and confirmed that there is a known issue with Intel VT Quad Port Adapter when configured to work with Trunk ports.They told me engineering are working on it.
A temporary work around would be working with access ports only, or using the 2 onboard nics for VST and the quadport for the Service Console and VMotion with EST(external switch tagging).