Hello,

 I have been facing a problem with NICs going down temporarily and
 intermittently, and there's a possibilty the ixgbe driver plays a central
 role. The behaviour is depending on the type of switch at the other end.
 Looking for some expert advice here.

 In brief:
 - Intel 82599EB connected to Nexus 4900 switch works fine.
 - Intel X540-AT2 connected to Nexus 3064 switch works fine.
 - 82599EB connected to Nexus 3064, or X540-AT2 to Nexus 4900, have
   intermittent interface down events lasting a few seconds. There may be
   two such events one day, none the next, and 50 the day after, just as
   an example. Traffic levels do not seem to play a role, but then, with
   mrtg, I may not have the required resolution.

Sep  5 10:56:16 host kernel: ixgbe 0000:04:00.0: eth0: NIC Link is Down
Sep  5 10:56:20 host kernel: ixgbe 0000:04:00.0: eth0: NIC Link is Up 10 Gbps, 
Flow Control: RX/TX

 What could be the reason, and can I get debug info from the driver to help
 iwth understanding ? All servers run CentOS5/6 and the driver versions
 involved are 3.9.15-k, 3.17.3, and 3.18.7. While there are different server
 makes and models affected, this behaviour definitely follows the NIC+switch
 combination. During the event, there is zero traffic through the interface
 (according to tcpdump), as you would expect with link down.

 My current working theory is that flow control settings may be the culprit.
 All servers have RX/TX on. The Nexus 4900 has RX/TX on, the 3064 off. I found
 that ethtool doesn't allow me to switch RX/TX off unless I also switch autoneg
 off, so I'm reduced to playing with the resp. switch settings. I take it that
 flow control (layer 2?) is not something that is autonegotiated between
 NIC/driver and switch?

 Any ideas?

 I only came across this list a few days ago. Neither Cisco nor Intel community
 forums have been any help so far.


------------------------------------------------------------------------------
Slashdot TV.  
Video for Nerds.  Stuff that matters.
http://tv.slashdot.org/
_______________________________________________
E1000-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/e1000-devel
To learn more about Intel® Ethernet, visit 
http://communities.intel.com/community/wired

Reply via email to