So we got ourselves a nifty 50Mb point to point comcast EPL for backup/DR. Specs on a EPL

http://business.comcast.com/enterprise/services/data/ethernet-private-line/EPL_Tech_Specs

So one of the interesting things about it is that it will just discard packets if you go over the 50Mbit/sec limit

So, I need some bandwidth shaping to make this work. I tried all sorts of things. At first if you just plug two computers on both ends I was getting really strange results. I think for a 50mbit connection they prob configure it to be 100Mbit speed and then limit from there. If you plug in gigabit on both sides you get really strange behavior, like 200KB/sec transfer rates.

So on the juniper I want to limit it to a 100Mb connection. To accomplish that log in, type CLI

 configure (set the ports to port-mode access otherwise your switch is a brick)

edit interfaces

edit ge-0/0/0

edit ether-options

set no-auto-negotiation

set link-mode full-duplex

set speed 100m

Ok, so that gets the speed set right, but now we need to shape the traffic.

so get back to the root level

edit class-of-service

edit interfaces

edit ge-0/0/0

set shaping-rate 50m

commit