[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Frustration (cablemodem woes)



On Sat, Nov 10, 2001 at 11:26:26PM -0700, Michael Patterson wrote:
> Ok, I'm totally frustrated. To bring anyone who doesn't know up to date:
> 
> My previous service was "wantweb". I was given a static IP address, upon
> which I set up a debian (potato) box. I used IP masquerading to connect all
> my windows boxes to it (for game playing, you know).
> 
> Now I find that the company is going under. enter the cablemodem. I have
> cablemodem service with Adelphia cable. ( @home). it works beautifully when
> I hook up a single windows machine to it, using DHCP.
> 
> When I hook up my linux box to it, I get terrible performance, and
> eventually my connection to the cablemodem fails. I can get the connection
> back by powercycling the cablemodem. I'm using dhcp-client.
> 
> DHCP appears to be working find after changing my /etc/networks/interface
> to:
> 
> iface eth0 inet dhcp
> 	hostname "****"
> 	leasehours 1
> 	leasetime 3600
> 
> ifconfig verifies that I have an IP address, etc. (and, as I said earlier,
> the connection works fine, but with poor performance, and eventually
> dropping.) When the connection stops working, ifconfig reports the same IP,
> etc, but starts reporting drops.
> 
> switchig to a static address, using what DHCP gave me still gives the same
> results.
> 
> I'm finding this EXTREMELY difficult to debug, since it isn't an out-and-out
> failure. The cablemodem howto isn't much help, either. Any help would be
> appreciated.

This sounds to me like a physical problem. You don't mention what
brand CM you have, but some CMs have difficulty communicating with
certain NICs. If you're not using the same cable each time, it might
be a cabling problem.

I'd swap the NIC in the linux box.  Try using the one from the windows
machine.

The only red-flag I see is your statement "When I hook up my linux box
to it, I get terrible performance, and eventually my connection to the
cablemodem fails. I can get the connection back by powercycling the
cablemodem."  Do the lights change on the CM when this occurs?  One
light shows whether the CM has sync with the cable network, and
another light usually indicates presence of network (local ethernet)
link.  There may be other lights which indicate traffic, etc.  You
need to discover which lights on your CM indicate cable network link,
and make sure that light stays lit while you are experiencing your
problem.  If that light goes out, your CM is having an RF problem and
troubleshooting needs to begin there (which means you get to call the
cable company).

Good luck,

-- 
Nathan Norman - Staff Engineer | A good plan today is better
Micromuse Ltd.                 | than a perfect plan tomorrow.
mailto:nnorman@micromuse.com   |   -- Patton

Attachment: pgpHckyaX3JGm.pgp
Description: PGP signature


Reply to: