Teaming Network cards = more speed?

Caporegime
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Ok I have been googleling this for the last hour and it seems there is conflicting info about whether setting up team increases transfer speeds


This guy here reckons the transfer speed is massively increased when he teamed his cards to 3GB/s



He said he transfered a 3GB ISO image in less than 20 seconds.

Now I have just bought a HP ProCurve 1800G switch that has

* Jumbo packet support: to improve performance of large data transfers

* IEEE 802.3ad Link Aggregation Control Protocol (LACP):

Could I get a boost with teaming? And if I bought say a Intel PRO/1000 MT Dual Port Server Adapter for my WHS?

Anyone tried this? Does it work?

Thoughts?
 
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Associate
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It "can" work, although 802.3ad isn't the best technology in the world, and the gains can vary vastly between different implementations/hardware.

To copy a 3GB file in 20 seconds however is a little hard to believe, he'd be averaging over 150MB/s throughput, something that he'd be needing quite a beefy disk subsystem for, even assuming that the transfer rate was even possible considering the overheads and efficiency of the network.

There are better implementations of NIC teaming out there, but you won't be utilising any of them with the switch you have.
 

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Soldato
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As a self confessed "specialist" in link aggregation i will try my best to .. elaborate.

Firstly, as per silworths "150MB/s" calculation - this is easily done on a single, 1000Mb link providing the server is fast enough, has good network interfaces (think FPGA etc) and a decent file system, etc.

LACP needs to be enabled on the switch, and on the server. What will happen is LACPDU's (Link Aggregation Control Protocol Data Units) will be exchanged, telling the each links partner/actor state how often it wants to recieve updates, etc. Now that the LAG (link aggregate) is set up, you will generally set up one of 2 types of aggregate: Static, or round robin.

Round robin will send packets 1,2,3,4 across links ge1, ge2, ge3, ge4 (for example!). Whereas static aggregation tends to deal more with "TCP Flows" - (Think circuit switched network); this generally means you are limited to a single point to point speed (i.e. 40Mbs Windows to Windows) but does save you cost of expensive switching hardware. Round Robin, setup over the LACP protocol should give you a speed boost - but bear in mind you will need a switch that supports it (Note: Cisco's new VPC protocol is LACP backwards compatible, VPC is being bundled with the next-gen Nexus switches).

Hope this helps.
 
Man of Honour
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Firstly, as per silworths "150MB/s" calculation - this is easily done on a single, 1000Mb link providing the server is fast enough, has good network interfaces (think FPGA etc) and a decent file system, etc.

Actually I'm fairly sure you won't get 150MB/s or 1200Mbps through a single 1000Mbps link, let alone easily...
 
Caporegime
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OK with a new HP Porcurve 1800G im getting this with two single gigabit nics and Jumbo frames on the switch


lan.jpg
 
Soldato
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Its my understanding that if you have 2 NICs that are teamed connecting to another server/switch with 2 NICs teamed, you'll still only get Gbit ethernet speed for each connection (using round robin)

E.g. So you can kick off one transfer of a ISO and it'll chung along at about 100MB/s, but you can then also copy another file at the same time, and this will also transfer at Gbit speeds too, essentially give you a 2GBit pipe.

If you want true 2000Mbps, you have to setup multipathing on your client/storage.

But then I could be totally wrong... :)
 
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Caporegime
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Its my understanding that if you have 2 NICs that are teamed connecting to another server/switch with 2 NICs teamed, you'll still only get Gbit ethernet speed for each connection (using round robin)

E.g. So you can kick off one transfer of a ISO and it'll chung along at about 100MB/s, but you can then also copy another file at the same time, and this will also transfer at Gbit speeds too, essentially give you a 2GBit pipe.

If you want true 2000Mbps, you have to setup multipathing on your client/storage.

But then I could be totally wrong... :)

Multipathing......Goes of to google :p
 
Man of Honour
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Its my understanding that if you have 2 NICs that are teamed connecting to another server/switch with 2 NICs teamed, you'll still only get Gbit ethernet speed for each connection (using round robin)

E.g. So you can kick off one transfer of a ISO and it'll chung along at about 100MB/s, but you can then also copy another file at the same time, and this will also transfer at Gbit speeds too, essentially give you a 2GBit pipe.

If you want true 2000Mbps, you have to setup multipathing on your client/storage.

But then I could be totally wrong... :)

Depends on the implementation/algorithm used - most hash the IP or Mac address, so if you do two copies they both use the same link (which is actually logical in many ways). None of them are really designed to allow aggregated speeds between two systems, but to allow multiple systems to use the aggregated bandwidth of a single host (ie. clients accessing a file server).
 
Soldato
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^ this. I stand corrected.

I think (and again, I could be wrong) If you want to get more than Gbit speed from your server, you need it (the server software) to offer iscsi targets to your clients, then you can use MPIO on your iscsi initiators to achieve, 2, 3 or 10Gb/s connections to your storage (depending on the amount of cards in your machines)

ANyway, teh video above is crap, he might be showing a 3GBit connection, but with only 1 client going to it, he'll only ever achieve 33% of that.

He's need 3 clients connected to use all 3 NICs.
 
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