teaming speed question

[Grahame Wright]

Hi there,

I have 2 DL360s with dual nics, and I've teamed them using the supplied HP utilities to create a single 200mb virtual adapter. This shows up correctly in Task Manager/Performance. The servers are connected to a Cisco 2950 switch, and I haven't done any configuration to team the ports on the switch side. Is it possible to get the full 200mb transfer speed during a single transfer (FTP for example). If I transfer a 1gb file from server a to server b, both with 200mb virtual adapters set up, is it possible to use all of the available bandwidth? Currently when I transfer a file, each server shows it's adapter usage at 50%, which looks to me like only one NIC on each team is being used. Any ideas?

[G. Vrijhoeven]

Hi,

Without knowing the OS. I know a bit ( not to much) about cisco config. If you configure a trunk ( channel in cisco terms) there are several way to set up load balancing among the interfaces. On port ( switch port level) server to server config ip-adress ( router to switch) and mac address level ( switch to switch). A copy from one file with ftp from one server to an other will use only one interface.

HTH,

Gideon

[Grahame Wright]

Both of the servers are running Windows 2003 server. So there's no way for me to get a "true" 200mbps connection between these servers, so that one single file transfer works at that speed and will max out both NICS in both servers? That's a shame...

[G. Vrijhoeven]

Ha again G.

I am not an expert on this, may be it is possible, but i do not know a way ( besides installing a GB card ) If your server communicates with multiple other servers the 200Mbit can be used.

Gideon

[Colin_29]

You will need to set up an EtherChannel on the switch. Check out http://www.cisco.com/warp/public/473/46.html#etherchannel it references possible issues with "EtherChannel and Trunking Between Catalyst Switches and NICs".

[ernst limbrunner]

hi grahame

a single connection CANNOT profit from any type of load balancing.

the port is selected by the mac or ip address. and as a single connection has only a single target address, all data will always go over 1 port.

you can find a whitepaper on this wspecioal question here:

http://h18004.www1.hp.com/products/servers/networking/whitepapers.html

best regards
ernesto

[Colin_29]

Ernst,

It's good to get an experts view on a subject like this. I always understood that a load balanced team shared the same IP & MAC Addresses and with SLB teaming through a Cisco switch, that traffic in both directions would be balanced.

Could you point me towards a more technical explanation as to why this is not the case.

Many thanks
Colin

[Brent_34]

The packets and Frames are being sent by 2 nics so in theory on the out you get 200MB.

The packets, frames being sent back to the virtual IP or virtual MAC are only addressed to one source. So double the load isn't being sent back to the team. This only enables 100MB on the return.

I believe switch assisted load balancing enables this through a supported configured cisco switch. This is also known as "Cisco Fast ether-channel"