Best serial console server construction method?

[Will Andrews]

Hi all,

In my quest to make my little network of computers more useful for
kernel hacking and testing, I'm attempting to build a very cheap
serial console server.  Basically, the idea is that I'm going to
use a computer that will be used for other purposes and add 8
serial ports.  How am I going to do that cheaply?  Well, N-port
serial cards (where N is >= 4) cost a few hundred dollars from
everywhere I could see (granted, they're niche items and are
accordingly priced).  So I came up with the following scheme.

If the computer in question has two USB ports, I could purchase
two 4-port USB hubs and get 8 single-port serial adapters.  So
far as I can tell, the total cost would be approximately:

8 x USB->RS232 DB9 Male	@ $8/ea =  $64
2 x 4-port USB hub	@ $8/ea =  $16
extra $ for misc. costs		   $20
			Total:	   $100
		Average per port:  $12.50

So my question is:  has anyone else done this kind of thing
before?  I am well aware of the flakiness in FreeBSD's USB
stack, but supposedly USB hubs and USB->RS232 adapters work
without a hitch.  If so, this could be the most economical
approach to building a serial console server.

Thanks for any comments.  Please Cc: me as I am not subscribed to
freebsd-hackers at this space-time vector.

Regards,
-- 
wca