We have a Metro Ethernet wan connection which seems to be auto negotiating at 100 half duplex. When I set the port to force 100/full the line protocol is down, when set it to 100/half or back to auto the link is fine. I’ve tried using another interface device, different cable and the same thing.
The vendor swears is our issue but I really fail to believe that. Could it possibly be something to do with our MTU size, which is 1500 ??