Cisco Switch, Broadcom NICs, Random Network Semi-dropping.

Discussion in 'Cisco' started by Teros, Jun 30, 2005.

  1. Teros

    Teros Guest

    'ello folks...

    So here's the situation. I'm in a company where roughly 100
    workstations, 15 printers, and 8 servers all drain into one closet in
    which we have a series of 3 Cisco 3500 XL switches (I forget exact
    model at the moment). The switches are chained together via GBICs with
    copper firewire. The workstations in the building are almost all using
    Broadcom NetXtreme Gigabit Ethernet cards (HP machines). At completely
    random intervals, a machine will drop part way off the network - for
    example, it will be able to ping servers A, B, and C, but not D, E, F.
    All servers are running fine and everyone else is doing beautifully.
    If I go to the switches and change the port the workstation is
    connected on, it can then see all the servers. If I plug a different
    machine into the original "problem" port, the new machine can access
    everything just fine.

    Any ideas? The ports on the switch are all auto-negotiate. The NICs
    are all auto-negotiate. The network cables shouldn't be the issue - it
    happens with new and old cords.

    We never had this problem until we moved to the Cisco switches. Before
    this, we had the same network setup, but with 3Com switches.

    I'm at a loss to what this could be. Any suggestions would be great!

    - Teros
    Teros, Jun 30, 2005
    1. Advertisements

  2. Teros

    Chad Mahoney Guest

    Is the workstations and servers connected to the same switch? If not
    maybe an issue with the trunk between the switches, do a sh int0/X to
    get counter stats for the port. Also it is recommended that you hard
    code speed and duplex settings instead of using the auto negotiate

    Post a sh int 0/X also what version of IOS are you running do a sh ver
    and post it.
    Chad Mahoney, Jul 15, 2005
    1. Advertisements

  3. Teros

    David Wood Guest

    We also have the same problem with (mainly) 5000 Cisco chassis but others as
    well. What seems to happen is when auto-neg is on the duplex often gets
    mismatched. I guess the card or the switch tries to transmit at the same
    time as receive and packets are discarded. Auto neg should be hardware
    controlled and was developed as NWAY a long time ago---but Cisco seems to
    have got it all wrong!
    Other switches seem to be very happy at auto (3com, Netgear).

    It's VERY inconvenient & time consuming to have to hard code - some devices
    may only have 10MB (eg. printers) and it's not following the design.
    Also in theory if the cable is dodgy the speed should be able to step down
    to 10MB
    David Wood, Jul 16, 2005
  4. Teros

    Martin Kayes Guest

    and if you look on the circuit board of some 5000 series cards you will see
    that the Ethernet chipset are Broadcom!
    Martin Kayes, Jul 16, 2005
  5. Teros


    Apr 20, 2007
    Likes Received:

    I know this post is old but I found it while googling for our problem....we have the SAME EXACT setup and problem.

    We have a 3500 Switch, and Broadcom NetxtremeII cards (but this time on our SERVERS) word for word it's the same problem (move to another port, it works for a bit, can ping a,b,c,d but not e,f,g, etc.

    Did anyone find a solution to this???

    rage1605, Apr 20, 2007
  6. Teros


    Aug 21, 2008
    Likes Received:
    Cisco Switch, Broadcom NIC

    Hi all.

    I know this thread is now VERY old, but we just ran into this in the last few months as a result of a switch upgrade. We replaced some very old switches with Cisco POE switches (specifically, WS-C3560's) We had previously deployed Dell desktops with Broadcom 10/100/Gig NICs.

    We discovered that (on our desktop machines, at least) the Broadcom NIC has two programs associated with it, the driver ("Broadcom Gigabit Integrated Controller") and a "Broadcom Management Program". Our problems went away when we removed the Management program from the desktop in question. I personally never would have figured this out, I'm not sure what possessed my co-worker Andrew to try it, but it reliably fixes the problem and after removing this our NICs auto-negotiate with our Cisco switches just fine.

    Hope this helps.

    lwhays, Aug 21, 2008
  7. Teros


    Apr 17, 2010
    Likes Received:
    Hi All,

    Once again, this thread is really old, but it gave me the answer to the same problem that I was having; thanks very much lwhays. I'm just learning Cisco routers etc, so was having trouble working this one out. Thanks very much for the post; removing the Management program instantly sorted the random dropping of the connection.
    twotony, Apr 17, 2010
  8. Teros


    Sep 30, 2011
    Likes Received:
    Just created this account

    Only to say thank you, thank you, thank you. I spent two entire days banging my head against the wall with this until I realized that all of the problem computers were using broadcoms!

    I have a cisco 3560g and bunch of different embedded broadcom nics. I removed the "Broadcom ASF Management Program" and rebooted. PC's all started working instantly.

    "lwhays" I would like to buy you a beer. Thanks.
    jimjawn, Sep 30, 2011
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.