Hi John,

You're not doing anything wrong - it's the load-balancing algorithm used by etherchannel that's causing you to use only one interface. In a nutshell, etherchannel does a hash on the last two bits of the source MAC address and comes up with one of four possible combinations. Your NDMPcopy connection starts up on only one port, using a single MAC address, so essentially there are no multiple MAC addresses to load-balance. Additionally, the balancing decision based on this hash is made by an etherchannel-enabled switch, not the Netapp box itself. Etherchannel requires all ports to be on the same switch and only really works when you have multiple clients (and consequently multiple possible hash combinations) accessing one server - it fails completely when you have a single "client" accessing a single server.

In brief, to get the best migration performance, use gigabit ethernet between two systems. You can simply reverse the optical cable leads - you don't even need a switch.

The good news is that more sophisticated load-balancing algorithms are under consideration, although I can't give you specifics or tell you when Netapp will have them available.

Good luck, Arnie

-----Original Message----- From: John Stoffel [mailto:john@casc.com] Sent: Friday, September 08, 2000 7:11 AM To: toasters@mathworks.com Subject: vif between 740 & 520 problems & questions

Hi all,

I've got a couple of questions on setting up and using vifs between two filers to help speed up data migration from the old F520 to a new F740.

They're configed like this:

F520 F740 OnTap: 5.2.1 OnTap: 5.3.6p2 RAM: 256Mb RAM: 512Mb Quad Ethernet Quad Ethernet Gigabit Ethernet

I've networked the two systems together using three ports on each Quad Ethernet board, but due to distance limitations, I'm going through three seperate hubs. So the two filers are basically hooked up back-to-back over a private network.

I did the various vif commands, and they are setup correctly, and they are passing traffic properly, but just over one of the three links. I know I need to upgrade the F520 to match OnTap versions, and will do so next weekend when I have some down time, but I wanted to play around with ndmpcopy beforehand to see how the performance will be.

Doing a test this morning, I managed to crash the new F740 with a PCI Parity error while doing another test of ndmpcopy. Whee!

My questions:

• will vifs work properly across direct connections between filers?

• Has anyone used a Lucent Cajun P220 switch to implement a VIF? I could easily run a fiber link from the F740 to a Cajun which would then run the three ethernet links.

And while I work for Lucent, the Cajun wasn't made in our division and I haven't used it.

Thanks, John John Stoffel - Senior Unix Systems Administrator - Lucent Technologies stoffel@lucent.com - http://www.lucent.com - 978-952-7548 john.stoffel@ascend.com - http://www.ascend.com