Sorry to hear of your issue but we have some questions. Has this ever worked on the this exact HW? Does ist work with another OS like RH, SuSE or Centos? Since it's a new system it may have never worked and you're just seeing it. What type of blade server is this? Please supply as many details of the system as you can. What type of switch is the port that is seeing the issue plugged into? Do you see the issue if you plug the NIC into another NIC (back-to-back)?
Please let us know and we might be able to help.
Actually we solved the problem today by comparing the code of v 1.2.20 (which worked) and 1.3.17 (not working). The interface is ok and stable, but we are not sure, if this change impacts other configurations. We'll provide the diff asap on the list.
The HW is a Intel Modular Server and the blade itself is a MFS5000SI. The dual ethernet controller is on the mezzanine board and the switch is the integrated one.