Mellanox Connectx-2 weird issue

[Biffa]

I've been using Unraid for a while, and added a Mellanox MT26448 about a year ago in a peer-to-peer set up with my desktop.

 

All worked fine for a while, then about 4 months ago I started to hit an issue where although the card was showing in Unraid and Windows, the connection wouldn't work. Initially, disabling and re-enabling the card in Windows would sort this out.

 

About a month later, this stopped working but I found I could still get the connection working again by stopping and restarting the Workstation Service in Windows.

 

Now, I can't get the connection working at all. I've tried using a different cable, but no joy. The card shows fine in Unraid:

 

[15b3:6750] 04:00.0 Ethernet controller: Mellanox Technologies MT26448 [ConnectX EN 10GigE, PCIe 2.0 5GT/s] (rev b0)

 

eth1 shows as up (no 'Interface Ethernet Port 1 is down. Check cable!' message showing).

 

In the Windows machine the card there shows as working properly, but status shows packets are sending, but not receiving.

 

I did at one point manage to get it working by removing network.cfg in Unraid and starting from scratch, but it lasted less than a day.

 

Has anyone experienced anything similar? Or has any ideas what might be causing this?

[Biffa]

I've tracked the latest issue down - for some reason my Unraid card was getting an IPv6 address, even though the Network Protocol option was set to IPv4 only. Changed this with ifconfig and the link works, so I'll scrub the network.cfg again and see if that works consistently.

 

I'm not sure whether this was related to the original issues I was having though.