FC3 box brings lan to its knees

[Marc McAllister]

Hi all,

New person to the list but a long time RH\FC user.

My setup:

ADSL modem/router
|
5-port switch
|
-------------------------
|           |           |
XP box   FC2 box   FC3 x86_64 box (AMD64)

The FC3 Test 3 box used to be running 2003 Server and it worked fine, I have
used exactly the same network settings as before.

I installed FC3 last night, it seemed to install fine. When I boot it everything
is fine, but when I try to browse the net or ping another machine it fails and
then causes the rest of the lan to fail too (not able to browse net, log into
the router, ping etc). If/when I take the FC3 machine offline everything
returns to normal on the lan and the other machines can browse the net etc.

I woke up this morning and thought it may have been a SMB issue, but I booted
the FC3 machine and checked, SMB wasn't running and the symptoms are still the
same.

Does anyone have any ideas, please?
Regards,
Marc