Microsoft Windows 2003 Server NLB

Posted on 2012-09-01
Last Modified: 2012-09-17

I have been asked to setup NLB on two boxes set for Terminal Services and whilst i done it many years ago on Win2000 things have obviously changed.

My question is would you use Unicast or Multicast?

The current setup is 2 NIC's per server, 1 each for NLB, the other two normal traffic. All 4 NIC's are being fed into a HUB, not a switch and then this is uplinked to a Cisco 2948G-G-TX network switch, this all works well.

Now we tried the above in a switch and things didn't work too well but we now should be using a switch on the newer boxes rather then the hub so i seek advise on how the "experts" would configure it.

Any help most wecome.
Question by:tmaster100
    LVL 30

    Expert Comment

    No way you should be forced to use a hub.
    A hub is half duplex and defeats every almost advantage the switch gives you.

    You should be able to plug into the switch and do your NLB from it,if that doesn't work,you need to use the NLB software that came with the NIC's in the servers.

    One or the other.

    Sounds like you had issues with duplex settings with gig-e,it's auto only on the switch and the NICs and nothing else, period!
    LVL 1

    Author Comment

    The Hub is a 100Mbit version, old and outdated, it must go but so are the two servers connected to it.

    I guess i need to decide if i put the LNB NIC's on their own switch and put the other NIC's directly on the Cisco 2948G-G-TX or would i put all 4 NIC's on a seperate switch and then uplink this to the Cisco 2948G-G-TX.

    Even though the 2948 is a switch i have heard using Unicast mode you can still flood switches.
    LVL 30

    Expert Comment

    Those are very good switches,and I doubt if you can flood them no matter what.

    The only way you could have an issue .is if you've got a loop ,and with spanning tree(portfast) turned on,that's not very likely.

    To use the NLB built into  the Cisco switch,you must plug the NIC's into the ports on that switch.

    You paid a lot of money for those switches,I would use them for NLB .

    Cisco is a pain in the butt to configure and is expensive,but generally speaking ,their products do work well.
    LVL 1

    Author Comment

    Ah, so what your saying is not use Microsoft NLB but connect one each NIC from both servers into the 2948G-G-TX and configure the switch to handle the load balancing?

    Never done that before, will need to research.
    LVL 30

    Accepted Solution

    Follow the  link.let the switch do the work,you paid for the feature when you bought it.

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