Finding the VM's assigned NIC

[jbsengineer]

How I understand Port ID load balancing is that the ESX server will assign a VM to the specific NIC in the team. I would like to know how I can find out which NIC is assigned to a particular VM. We are working with our networking guys on an issue with MS NLB and we need to find some things out. We already have looked at the router/switch arp tables to find out where it sits but I would like to find out on the ESX side.

[mike_laspina · Accepted solution]

Hi,

The method you used is currenlty the only way to determine what network path the mach is assigned to.

[apatel1]

You could use the esxtop command (in "n" mode) to look at the throughput of a VM and then try to match that to a particular pNIC. For example, if VM1 was pushing 100Mbps according to esxtop, and you saw that vmnic2 was also pushing 100Mbps while the other vmnics were more ore less idle, you could say with reasonable confidence that VM1 was using vminc2.

Hope that helps! Please help me out by marking my response as "helpful" or "correct" if you feel that it was useful!

-Amit

[jbsengineer]

Unfortunately I'm looking at production machines that aren't pushing enough network through to find it on ESXTOP. Also I can not intentionally push data through because of prod. But that's a good tip thanks!