[c-nsp] EMC Centera storage problems vs nexus 5K

[Arne Larsen / Region Nordjylland]

Hi all

I know it's a wild shot but I'll try anyway. I have some problems with nexus 5k and EMC Centera storage setup.
The setup form EMC has 2 links to the 5k one 10G as primary and 1 1G as secondary.
If the mount a nfs share and download with small files from that, they don't get more than 4-5 MB per sec in transfer. The client is on a 1G link.
But if the download big files they can max it out. The same test with 1G works fine. I know it's no problem to overrun a 1G link with 10G.
EMC claims that they se retransmissions, but I don't se any packet being dropped, on ether client or server interfaces.
I know that nexus 7K has a feature that can stop sending packet to an interface that is in overload and drop the packets in the fabric, does the 5K do the same ??, and if, how or where can I se that.
If any one has experienced something like this, I would be glad to know about it.

/Arne