In order to cut our usage of the OC-12, I've determined how to rate limit our switch.  This is very undesirable, but needed to prevent us interferring with other campus network usage.

a) log into the switch

b) enter enable mode:

    > enable

c) enter configure mode:

    >configure terminal

d) configure the network interface:

    >interface ethernet 4/1

(4/1 is the port that the OC-12 enters the switch.  This is port 1 on module 4.)

e) examine current rate-limits (if any)

    >show rate-limit

f) To change the rate-limit you need to clear the old limits first.  It won't overwrite limits already set (it complains).

    >no rate-limit input 400000000 500000000

The above is for an input limit of 400 Mbps with a burst limit of 500 Mbps.

    >no rate-limit output 400000000 500000000

Remove both the input and output limits.

g) Set new limits:

>rate-limit input 400000000 500000000

>rate-limit output 400000000 500000000

Currently these rate limits have not been written to flash, so if the switch is rebooted we'll once again have NO limits on our bandwidth usage.