14 Replies Latest reply on Oct 24, 2012 2:50 PM by cj! Branched to a new discussion.

    NV1238 High CPU utilization

    cj! Beta_User

      When I show processes cpu on a NV1238 PoE, we're constantly seeing 48-60%+ load for all three counters.  The switch is a couple months old and seems to have exhibited this behavior the whole time.  It's running ver 18.01.04 firmware.

       

      It has only six ports open and almost all ports use PoE.  Twelve ports are IP security cameras and they constantly stream video to a recording server on giga-swx 0/1.  The remaining 100Mbps devices are phones and phone server equipment with fairly low usage.  There is an LACP trunk using giga-swx 0/3 and 0/4 to our NV1638 core switch.  Giga-swx 0/2 is a VLAN trunk port going to a VMware server (primarily used for voice applications, which is why it's on the 1238 with the phones).

       

      No one is complaining about any symptoms, I just want to see what's up with this.

       

      I tried shutting down one of the LACP ports, then the other, just to see what happens.  But there's no change.  No reason to suspect LACP; just trying stuff.  Also, I tried shutting down the camera ports and the camera server port to see if eliminating the bulk of this switch's traffic would have an effect.  But that made no difference either.

       

      When I show processes cpu, the big offender is bcmLINK.0 and it's always around 30-45% load.  I'm not sure what this task is, but I think it's the culprit.  See the output example (TXT file attached).  CFG attached too.

       

      Thanks in advance!

      --

      CJ

        • Re: NV1238 High CPU utilization
          levi Employee

          CJ:

           

          Thank you for your questions.  I will review your output and configuration and follow up with you by close of business tomorrow.  Do not hesitate to reply to this post with additional information or questions before then.

           

          Levi

          1 of 1 people found this helpful
          • Re: NV1238 High CPU utilization
            levi Employee

            CJ:

             

            The "bcmLINK.0" is what the switch uses for a linkscan thread.  It is responsible for polling the physical interfaces and updating status.  One reason for this to be high could be if there are a lot of changes constantly happening on the network.  I would recommend removing the commands "switchport access vlan 7" from each of the "phone" ports.  I do not recommend having "voice vlan" and "access vlan" on the same interface.

             

            Levi

            1 of 1 people found this helpful
              • Re: NV1238 High CPU utilization
                cj! Beta_User

                I removed "access vlan" from all phone ports.  I wrote the config and reloaded (just for good measure).  Phones are now tagging VLAN 7; everything is functioning okay.  But the system load is the same, with task bcmLINK.0 remaining the culprit.  What should we try next?

                • Re: NV1238 High CPU utilization
                  mj_data New Member

                  Levi,

                   

                  I have a netvanta 1234 switch that is having similiar issues, with the exception being that my "bcmLINK.0" is only around 6%, while my bcmARL.0 is running around 25%.  Can you elaborate on what the bcmARL process handles?  I saw your summary of bcmLINK being a linkscan thread.  This switch is acting as a media converter basically, and doing only L2 switching.  MM fiber in, gig copper out, and thats it?  Also, the sfp that im using is from cisco, could that be an issue?  When the 1234 recognized, initialized, and ran it free of errors i assumed it was ok.  Thank you for the help,

                   

                  Mike

                • Re: NV1238 High CPU utilization
                  mj_data New Member

                  did you all figure out what the issue was on this?  im seeing this same behavior, with the jacked up processes being "bcmARL.0" and "bcmLINK.0".  whats odd is that this switch is doing nothing except basic layer 2 switching, am confused by it ??? am about to start updating the software, please post what ended up being the problem.  thanks