Thank you for your help in advance.
I've posted a few messages here before and getting helps on what I am trying to do. After actually testing it, it just flat out won't work. Here goes:
I am trying to use a ME3750 to terminate an internet 10MB pipe. According to the ISP and some people here this "should" work, but result shown otherwise. (Upgrading this pipe from 10 to 100MB, therefore, have to change out the ISP provided router and come up with something else) If the pipe is terminated with, for example, a 2811. I can set the WAN interface to 10MB/Duplex full and getting the full 10MB. No surprise there. I then used a ME3750 to terminate the same circuit. The behavior was that I could not set any duplexing or speed. If I do that, the interface promptly went down. If I leave both the duplexing and speed to auto, the interface would come up BUT with tons of CRC errors and I could only get 1/2 a MB on a 10MB pipe.
I am runnign out of idea here since this "should" work but it doesn't. Yes, I know, how about getting a 7200 series and be done with it but it just costs too much and I can't afford it right now. Too bad the 2811 can't handle the load on a 100mb pipe, otherwise, I don't have to even try to use a L3 switch in lieu of a true router.
Comments and help is greatly apprecaited.
this looks like to be a physical layer issue.
We had a similar problem in the past with a 10/100/1000 not able to work at 10 Mbps full with an ethernet over SDH device.
We solved by introducing a L2 switch with one port connected to the multilayer switch and the other FE set at 10 full towards the SDH device.
Both ports were in the same L2 vlan.
Hope to help