4 Replies Latest reply on Mar 18, 2015 7:20 AM by BillTheDBA

    CRC errors on our new gigabit Ethernet adapters


      We recently replaced some 1GB network adapters with HP 561FLR-T 10Gbit adapters. 1 went into a Windows server and the other 2 went into Redhat 6.6 servers. No issues at all on the Windows side. However, on the 2 Redhat servers, we get several thousand RX/CRC errors per day. I can find no apparent reason for this.


      Servers: DL380p Gen8

      NICs: HP 561FLR-T

      Driver version:  ixgbe-

      Switch: Brocade 10Gbit


      The two ports are bonded. So far, everything looks to have been recoverable. But it seems that if everything is done properly, CRC errors shouldn't occur at this rate. I'm kind of at a loss to understand or explain this. And given that the Windows server is in the same rack, connected to the same switch, with same brand/length/type of cables, it's even more confusing to me. So I'm looking for thoughts or ideas on what I can try next.


      Disclaimer: I'm not a network guy, but we're a very small shop so I've inherited the job. But I'm perfectly willing to accept that I've done something wrong as long as it solves the problem

        • 1. Re: CRC errors on our new gigabit Ethernet adapters

          Dear BillTheDBA,


          Thank you for contacting Intel.


          I understand you have upgraded your network card from 1 Gbps to 10 GbE speed.  Please make sure you are using a CAT 6 or 6A network cable.  You may also try to connect to another port and see if it can improve the network performance.


          You may refer to our website for the cable requirement for 10GbE connections here.


          I hope this is helpful.





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          • 2. Re: CRC errors on our new gigabit Ethernet adapters

            Hi Sandy,


            I verified that our cables are CAT 6A. So unfortunately that's not the issue. We even changed them out with others but no luck. It's only on our Linux servers where we are receiving the CRC errors. We have the same card in a Windows server and it functions flawlessly.

            • 3. Re: CRC errors on our new gigabit Ethernet adapters

              Hi BillTheDBA,


              Thanks for writing back.


              I see that the CRC Error happens only on Linux System.  We also suggest to use the Linux driver supplied by HP since you are using an HP network card model.  You may check for available driver for this NIC model HP 561FLR-T from HP's website.  In case you still encounter CRC errors, please provide us more information.  Error message (if any), where you see the error, etc.




              • 4. Re: CRC errors on our new gigabit Ethernet adapters

                Thanks for the suggestion, Sandy. I feel like that may be the best next thing to try. The reason I didn't use HP drivers initially is because we're on Redhat 6.6 and HP currently has drivers only up through 6.5. But reverting to 6.5 isn't that big of a task, and if it gets rid of the CRC errors, then I'll be happy.


                I'll keep you posted with my results. I may have to wait until this weekend to perform the rollback of Redhat.