Problems with Fedora and cable modem

[Aleksandar Milivojevic]

I have a problem with my Fedora box and cable modem.  I'm not sure if 
the problem is on my side, or ISP side (Shaw cable).  Of course, ISP 
claims it is not them, what else would you expect ;-)

Basically, what happens is that dhclient obtains IP address for my 
external interface.  Than everything works fine for some period of time 
(less than a half an hour), and after that I loose all Internet 
connectivity.  If i restart dhclient (for example using "ifdown eth0; 
ifup eth0"), my PC gets IP address reassigned (in my case, I'm always 
getting same address, 24.79.220.4), everything works for a while, and 
than it stops again.

Something like this happened about a month ago, and restarting the 
interface solved the problem.  Yesterday it started to happen again, but 
this time restarting the interface solves the problem for about a half 
an hour, and than there it is again...

I have two more interfaces on this Linux box.  One is toward my internal 
network, and another is toward DMZ.  Those two have static IP addresses, 
and everything seems to be working fine with those two.

What I have observed when this happens, is that I can sometimes ping the 
router on ISP side (24.79.220.1), but nothing else.  Sometimes. 
Sometimes ping to ISP router doesn't work at all, or works partially 
with large percentage of lost packets (95-99% range).

Anybody else had similar problem?

-- 
Aleksandar Milivojevic <amilivojevic at pbl.ca>    Pollard Banknote Limited
Systems Administrator                           1499 Buffalo Place
Tel: (204) 474-2323 ext 276                     Winnipeg, MB  R3T 1L7