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Emulab FAQ: Testbed Operations: What can I do about switch port problems?

Emulab FAQ: Testbed Operations: What can I do about switch port problems?

> We have had a few cases where a simple 2 or 3 node topology with delay
> links is created, but the nodes can't talk to one another. It looks alot
> like a cable problem, and in one case that was true... but It is
> intermittent enough that I would be surprised if this were the case in
> all situations.  At any rate, some sanity check of each of the links on
> a node, and all of the ports on the switch, might be warrented before we
> allow folks back on the platform.

A few things:

1) There is a script on boss, checkports, that you can give a pid and eid to, and it will check to make sure that all switch ports in the experiment have carrier and are running at the right speed.

2) There is a script on boss, switchmac, that will report on the MAC addresses that the switch has learned, and match those up with what we have recorded for the nodes' interfaces. The catch is that the switch will only learn MACs on ports that are enabled, of course, and forgets them after a while, so you'll only see recently-active interfaces.

3) The scripts for adding nodes to the database use switchmac to automatically figure out what is plugged into where.