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tripwu
5th July 2007, 07:08 PM
Hi Guys

Does anyone know much about link aggregation under OSX, would like to combine 3-4 gigabit links in each G5/Macpro so I can get a decent throughput to our Raid from multiple machines.

Raid im setting up can pull about 600MB each way locally, would be great to get over 200MB/sec transfer over the network.

anyone done this stuff before?

unfortunately we dont have the funding to go fibre.

otherwise, when are these rumored 10gigabit NICs going to be available for a decent price.

zbaron
5th July 2007, 08:58 PM
I don't think it is free, but http://www.small-tree.com/ have information about doing link aggregation on OS X -- although, it looks like they'd recently changed their web site and I cannot find it now. They also offer 10Gb cards.

Don't forget to enable Jumbo ethernet frames if all the machines are going to be on the same subnet and switch, and make sure the switch can handle the 9000 byte MTU as well.

dotnet
5th July 2007, 09:00 PM
OS X supports link aggregation out of the box, I don't know the maximum number of physical links supported, though. Also, see this link (http://lists.apple.com/archives/Darwin-dev/2007/Jan/msg00040.html).

Cheers
Steffen.

zbaron
5th July 2007, 09:07 PM
OS X supports link aggregation out of the box

Cool! I'll have to look into this.

It is possible that aggregating the two links does not equal a 2Gb/s port, i've found in Cisco land that etherchannel is closer to load balancing links, so a single data flow will only go as high as one of the links, leaving the others for other data flows. Could be the answer to the above question.

dotnet
5th July 2007, 11:12 PM
Cool! I'll have to look into this.

It is possible that aggregating the two links does not equal a 2Gb/s port, i've found in Cisco land that etherchannel is closer to load balancing links, so a single data flow will only go as high as one of the links, leaving the others for other data flows. Could be the answer to the above question.

It is load balancing the parallel links. However, layer 2 doesn't have a concept of data flows. Sure, you can't split a single ethernet frame and send its parts over the individual links in parallel, but you can send whole ethernet frames in parallel.

Cheers
Steffen.

mac_man_luke
5th July 2007, 11:20 PM
I believe all you need is a switch that supports it - some g5s have dual ethernet standard

tripwu
5th July 2007, 11:25 PM
cool thanks guys, from what i have read so far, it looks like i wont be able to get a single stream of data at more than 1gigabit.

still worth doing it on the server, but not much point for the other workstations.

might have to get sata arrays to put on each, will be doing uncompressed HD colour correction, and general digital intermediate stuff need around 220MB/sec.

was hoping we could do it all on one big drive, so we could speed up the workflow.

guess thats why everyone else is having to buy Xserves and fibre channel switches/nics etc

dotnet
5th July 2007, 11:45 PM
was hoping we could do it all on one big drive, so we could speed up the workflow.

guess thats why everyone else is having to buy Xserves and fibre channel switches/nics etc

One big drive couldn't provide that sort of bandwidth anyway, but a 4-slot eSATA case could, if you RAID-0 the four disks. Like the Sonnet Fusion + matching eSATA card.

Cheers
Steffen.

tripwu
5th July 2007, 11:48 PM
yeah, what i meant, was one array ...its a 16 drive RAID 5

dotnet
6th July 2007, 12:29 AM
yeah, what i meant, was one array ...its a 16 drive RAID 5

Wow, you don't muck around ;)

Cheers
Steffen.