100 Days - Day 10 - iperf on 10GbE Connections

Tue, Jul 5, 2022

Setup and First Tests

With both PCIe cards now working, I wanted to do some quick verifications that the 10GbE interface was being used. I hooked up my R730 and Supermicro 2U server to my switch with a DAC cable. I search around the internet and found this brief guide on using iperf. I downloaded iperf3 on both machines with apt install iperf3.

On the R730 running Proxmox, I ran iperf3 -s and on the Supermicro Server I ran iperf3 -P 20 -c <ip_of_proxmox>. At first, I was a little disappointed, as I was only getting 1GbE speeds or ~940Mb/s.

[SUM]   0.00-10.00  sec  1.10 GBytes  946 Mbits/sec 9470             sender
[SUM]   0.00-10.00  sec  1.10 GBytes  941 Gbits/sec                  receiver

The Fix

I realized that this was because the main bridge on Proxmox was still using the 1G Ethernet cable. I made the change from en01 to enp130s0f0 in the Node -> Network tab, but was surprised that on a second test, nothing had changed. Hint: you have to press “Apply Changes” to make anything work. See the Proxmox Docs.

Second Test

With that out of the way, I ran the test again to get a much more satisfying result:

[ 44]   0.00-10.00  sec   351 MBytes   294 Mbits/sec                  receiver
[SUM]   0.00-10.00  sec  11.0 GBytes  9.41 Gbits/sec                  receiver

And there you have it. Once I get things locked down a little more, I may try to get 40GbE NICs for these two machines, but that is a later quest. I'm getting a little tired of thinking about hardware and will jump back to some Kubernetes and Ansible studying tomorrow.