Gigabit Connection RRS feed

  • Question

  • Hi,

    Has anyone seen this behaviour - or can explain it?

    I have an HP Mediasmart Server EX470, it is connected to a Netgear GS105 5-Port Gigabit switch.

    If I use the Network cable supplied with the EX470 the latter will establish a Gigabit-speed connection with the GS105, when I power-on the EX470.

    If I use an existing Network cable, the EX470 will only establish a 100 MBit connection when switched on.

    However, note the following additional info:

    The existing Network cable works quite happily at Gigabit speeds when connecting various of my Dell PCs (with Gigabit NICs) to the Switch - using ANY of the switch ports.
    Having established a Gigabit speed link using the HP-supplied cable, if I then swap it for the existing cable, the link STAYS AT GIGABIT speed - even following a soft reboot. If I powercycle the EX470 then the speed drops to 100 MBit on restarting with the existing (non-HP) cable.
    If I powercycle the Switch, the EX470 re-establishes a Gigabit-speed link with the existing (non-HP) cable.

    It would appear as though there is something about the HP cable which allows the EX470 to negotiate properly with the Switch.

    Any thoughts?

    BTW - The obvious soultion of "just use the HP cable" is unattractive to me, because the existing cable is nicely dressed and neatly tucked away with all the other network cabling.
    Using the HP cable means I have a bit of loose cable dangling about looking untidy and even if I went to the effort of dressing it with the other cables, it would be too short for the "tidy" route between the Switch and the HP.

    Thanks in advance for any help.

    Friday, March 28, 2008 1:22 PM

All replies

  • Gigabit networks require CAT5e or CAT6 cable. I know that many "existing network cables" that I have just laying around are only CAT5 (and not CAT5e or CAT6). That cable supplied with the EX470 is CAT5e. I suspect that this is your problem so check the printing on the cable.

    Friday, March 28, 2008 3:08 PM
  • There's nothing magical about the HP cable. It sounds to me like there's a problem with your other cable. You could try other loose cables to prove that the HP cable isn't magic. If you actually have a reliable connection over the one that's dressed with the rest of your cables, you could also try forcing the HP MediaSmart Server to 1000 Mbit instead of autonegotiating. But I would bet that you don't have all that reliable a connection; you're probably seeing significant packet loss or corruption at that speed with your dressed cable.

    Friday, March 28, 2008 3:11 PM
  • To establish a gigabit connection you do NOT need to buy fancy cables, standard cat 5 cables work very well unless you want to run the cables long distances. If you only run the cable around your office cat 5 is fine. However you must ensure that all 8 wires are connected, if you don't then all you get is old fashioned 100Mbps.
    Friday, March 28, 2008 9:28 PM