2 NICs with same IP address?

[ZK]

Hi there,

Any help is much appreciated.

Would anyone be so kind as to explain whether it's possible to "team" two Intel Pro/100 Management NICs in Windows NT with the same IP address?

The cards are already in the machine, I just don't know how to team them together.

Thanks
ZK

 

[FairbanksF]

Not a good idea to give two nics the same IP address. ARP will have a hard time distiguishing between them.

 

[DiscoDuane]

Download the latest Intel drivers from their site and when the servers updated go to control panel and doubleclick on the Intelpro icon theres and option in there to team them up

 

[arcIT]

Yes, it is possible. You first need to make sure your using sp3 or higher.

 

[quork]

What would be the benefit in doing this?

thanks

 

[Zelandakh]

Greater throughput of data. Half duplex each card so one is out and one is in. Or whatever. Get 200Mbs for the server (or more).

4 NICs on one IP using the Intel software means 400Mbs for the server... cheaper than getting Gig cards...

 

[Pathogen]

can someone give some more info on this? or a URL?

surely this affects other equipment on the network?

cheers

Bill

 

[drvanhelsing]

You'll need to configure the switch for this ideally (so i'm led to think). There is some other off-the-shelf software (i think it's called balance) which facilitates 2 nics in the machine - you could get 400Mbps throughput from 2 cards though, if you enabled full duplex as well (theroretical throughput). We've got some Intel dual port nics in some compaq servers, but haven't configed the second port yet. i'd be interested to hear how you get on.

 

[Pathogen]

I'd be interested too, it sounds messy.

surely it messes up arp entries on other machines on the network too.

I had a quick look at the Intel website and couldn't find anything about it.

 

[peterve]

You can use Microsoft WLBS Load Balancing service as well to do this Peter Van Eeckhoutte
peter.ve@pandora.be

 

[Guest_imported]

You can't have 2 cards on the same network with duplicate IP address. The best thing to do is to have to different IP addresses on the same subnet and then add the addresses onto your WINS server as multihomed. This will allow anything connecting to the server in question to look at the 2 addresses availabel to connect over.
I had a simular problem although the 2 cards were pointing at different subnets.
Hope this helps...

 

[Pathogen]

aahh, it's all making sense now, thanks.
I thought i was going mad !
I thought i understood IP until i started reading this thread, now you've confirmed that i do... phew

cheers

 

[jmartin]

Sure, I thought IP protocol was so easy to understand, but I never heard that maybe be used two cards with same IP address on a server.Where could I find more about this?

 

[DiscoDuane]

The Intel pro server NIC card has the ability to be teamed up. Once you install the card and software there is an option in control panel for the INtel adapters this will walk you through teaming them up
Both cards get a unique ip address but the software lets them act as one

 

[masai]

There are 3rd party software that provide the service. Try the NSI site:

http://www.nsisw.com/pages/brmenwin.htm

 

[wallerkr]

We use the Intel adapter teaming for redundancy (each to a different switch just to foil Murphy!).

 

[Budgie69]

On the Second network card do you need to connect it to the network, ie same hub as the first card?

Thanks

 

[MarcS1]

When you team adapters the software (Intel Drivers) creates a virtual NIC to which you assign the IP Address. You dont have 2 cards with duplicate addresses you have two cards Masked by a virtual nic. So no problem

 

[dreamgirl]

.Sorry to mess this up even more but you can have two network cards with address on the same subnet. Teaming the NICs means that each network card has an seperate IP address (so that ARP is ok) and then there is a 'virtual' IP address which is used as the contact for the server and is the only IP address that is ever seen on the network. I know it works because I have it running on my network.

 

[dhwebb]

Right. There are more ways to do this also.

Compaq Teaming Nics allow for mac sharing, what this does is it add's a third nic, virtual of course, and it has it's own seperate mac address. Through the software, both nics listen for this same address and the software decides which nic receives it.

You can also use Fast Ether Channel with some switches. This takes away the software portion of "which nic accepts the packet game" and lets the switch do it. This will give you the best throughput because in the earlier example, the switch sends all the packets to both nics, where Fast Ether Channel only send to 1 of the nics. That is how you get 200/400/800 mbit connections.

Finally, the multihomed wins entry is a good idea too if you use standard nics and switches/hubs. The only downfall, you don't get true load balancing. Because once a pc caches a netbios address, it will keep using it. If half go to one ip and the other to another, what if the first half are power users and the others e-mail people basically. The other card is sitting idle. I have never done this, but I can tell from other experience, this is the least effective solution.