some really basic networking questions -- solved

[dep]

well, you wouldn't believe it. i barely do, and i saw it.

it was a hardware problem. and not just that, a physical hardware 
problem.

the dongle on my intel pcmcia ethernet card attached just loosely 
enough to the cat-5 connector that if it's inserted one way -- with a 
twist that is not readily visible -- the connection is broken. but if 
it's inserted the other way -- without the twist -- the connection is 
good. and i apparently pick up the card and insert it with the twist 
just about half the time.

dhcp does in fact rewrite /etc/hosts. everything works as everyone 
here predicted. hotplugging works. i even switched network cards and 
all works.

and the problem would have happened with any connection on any 
machine. but the tp-240 has its pcmcia slot on the left, at the 
front, while all the other notebooks i have used the card with have 
it at the right, on the back, where the tension on the connection 
doesn't come into play.

it's a frigging loose connection that coincided with the several times 
i tried different things. unbelievable.

thanks, everyone, because i've learned from all of you, even though 
the problem was, well . . . embarrassing.
-- 
dep

http://www.linuxandmain.com -- outside the box, barely within the 
envelope, and no animated paperclip anywhere.