UCS C240 10GB NIC Tx only 74mbps TX rate

[Bobby Mazzotti]

I have somewhat a unique customer configuration I'm troubleshooting. My customer has a C240 and C230 UCS storage servers directly connected to each other over an Intel ethernet converged network adapter X540-T2. So they have a Cat6 crossover connected NIC to NIC, but they are only getting 74mbps throughput. 

Things done for troubleshooting -

 + Updated intel driver to the latest

 + Changed speed to 10GB Full duplex both servers

 + Changed Intel performance settings -

     - Receive buffers 2048

     - Transmit buffers 2048

Windows reports the connection via properties as 10GB, but still not getting the performance I expected. Any thoughts on what could be causing this issue?

Thanks,

-Bobby

[Walter Dey · Accepted solution]

Which OS and version / patch level ?

Which tool do you use to measure performance ? memory to memory ?

[Bobby Mazzotti]

I believe the issue was they are using a Cat6 crossover with only 2 pairs crossed. This would result in 10/100mbps speed. I had them purchase a straight-through Cat6a cable in hopes the MDI/MDX would allow the connection to pass 10GB.

 Intel® Ethernet Converged Network Adapter X540 Series T2

is the model.

[Bobby Mazzotti]

Well still no luck. Transfer replication rates are still in the low 74mbps.

Windows OS: Windows Server 2012 Enterprise R2.

RAM 256GB, and CPU is Quadcore 3.2 MHZ.

We use a replication software called SIOS, and I've use LAN speed test, and Windows performance resource monitor. Average replication speed from SIOS has been roughly 2.6GB a minute or less.