Upgraded to 2960G from old Netgear GigE and lost throughput

[d.lewis]

I've been working on this issue for a while now and haven't gotten anywhere. My old GigE Switch (on copper) gave me about 3Mbps server to server, and I expected when I upgraded to the 2960G that I would seen an improvement in this, however the opposite seems true. In Most cases I lost 1Mbps. It's almost like it's process switching every packet, it just doesn't seem to have the throughput that I would have expected. Am I nuts ? or did I miss something in the config. All ports on the switch and server are 1000 Full Dup hard coded. Ip route caching is turned on, on the vlan, other than that, it?s basically a clean config. I'm lost. Any ideas anyone ?

[dan-jones]

You can try the PCs with a crossover cable and see if the speed changes. 3Mb/s is poo...I'd expect that on a 10Mb/s hub. Have you tried setting the NICs and switch ports to 100/Full as a test?

Also, one other thing, if these are Windows XP machines, check this: http://support.microsoft.com/?kbid=842264 (dunno if you have LSO or not)

[glen.grant]

Leave the server and switchports set as auto for speed and duplex and retest . Check to see if you are seeing any errors on the ports with the "show interface counters errors command . Also do a "show interface status command and see how the ports are actually negotiating .