Network Backups - which network used on VM host?

[TaylorB]

I'm having some network performance issues on one of my 2 VM clusters. I'm getting about 13 MB/s throughput from one cluster, but the expected high speed 115MB/s from the other. I'm trying to troubleshoot the huge discrepancy and I was wondering if anyone knows which network connection on the VM hosts that the backups are using. I can't seem to tell whether it is the Management port or the VMkernel that sends the backup traffic to the Veeam server.

Thanks in advance.

[TaylorB]

After poking around the FAQ, I think I may have answered my own question with this post:
Network backup slow on vSphere ESX 4.0

My slow cluster is still on 4.0 and my fast cluster is on 4.1. According to that thread, 4.0 has some bandwidth throttling issues with the management port that can cause slow backups.