Network Performance issues - no errors

[jhale]

We have a fully redundant core on 6509's with MSFC on each for IVR. Access layer switches connected to the collapsed core /distribution layer are 4506's with RSM's. I have 3 servers connected to the core / dist switches with redundant gig interfaces. If I copy file to server speed is very very very slow. 0.03 MBPS. I am copying from Core switch port; access switch port; it does not matter. Performance is the same either way. If I push file from server to client speed is lightning fast. Here are some stats:

server to workstation 100 meg file 20 seconds

workstation to server 100 meg file 38 minutes

Any ideas on what the problems may be?

I have HSRP running;

All switches are fiber uplinks;

any ideas or thoughts would be appreciated.

[tbaranski]

Make sure there isn't a duplex mismatch on either the server or client port (or any intermediary uplinks). Either force both sides of each link to 100/full or leave them both at auto -- forcing one side to full duplex and leaving the other at auto results in a duplex mismatch which generally entails very low throughput.

[arubino]

I have expierenced a similar issue. Access layer = 4500 with dual gige fx connections to collapsed core / distribution. Span-tree forwaded on 1 of the gige links. transfers fast in one direction and slow in oposite direction. our problem turned out to be bad fiber. after the deep freez in chicago, a warm spell hit and effected 1 strand of the fiber pair.