I am running a 3640 at a co-location facility. It is running Version 12.2(5a), RELEASE SOFTWARE (fc1). How do I tell what the port speed of the interface is set to? I've printed out the config, and it just tells me that it's full duplex. I did a "sh interfaces" and it doesn't tell me what the speed of the link is.
If it is a FE it will be 100MB by default , you can change the speed to 10 MB by using the 'speed 10' command , you may want yo chaeck the device this is connected to to make sure your speed and duplex setting match .
The default value of the speed of the link will be indicated under show interfaces command by the "BW" parameter. If its a fast ethernet interface and if you have the speed set to default, then it would indicate as 100000 Kbit, which is 100 mbps. If you change the speed using the "speed <10/100/auto> command, and change it to 10 mbps, the BW parameter will reflect the change as 10000 kbit which is 10 mbps.
Hope that helps