[olug] ping modem

[Rob Townley]

On Jan 23, 2008 11:24 PM, Tim & Alethea Larson <thelarsons3 at cox.net> wrote:

> Luke -Jr wrote:
> > On Tuesday 22 January 2008, Tim & Alethea Larson wrote:
> >> I keep losing my connection to the outside world, though my LAN is fine
> >> and Cox says my modem is fine.  Usually I end up resetting the modem
> and
> >> sometimes the routers too.  There's got to be something wrong between
> >> the modem and the router.  How can I troubleshoot what it might be?
> >
> > Try 'mtr'
>
> I've not heard of that one.  Would the modem have a LAN IP that I could
> ping at?  Seems an obvious thing to try.
>
>

http://192.168.100.1  i have found to be the standard cable modem web page
accessible from any PC on the private / inside of the the network whether
directly connected to the cable modem or through a nat device.  It doesn't
matter what brand and not just in North America, because i found this to be
the case when visiting some East Asian countries, India, Turkey, Europe....

The web page has a Logging tab that sometimes will monitor for drastic
changes to the Signal to Noise Ratio for both upstream and downstream.
However, the forums will give different answers for what these values should
be.  Probably because it depends on how much power has been supplied to your
neighborhood and what the CMTS needs.   Under "Addresses", it will help to
verify how many ip addresses cox will allow you to have.   Below is from
behind a business that has 3 IPs.  In older versions, you could tell the
cm DHCP server to let go of certain MAC addresses which made it much quicker
to then tell your PC or Nat dhcp client to renew without having to power
off.  Think of the situation where you need to switch from one PC to
another.  Further, connecting via both USB and Ethernet WILL cause problems
because COX will think you are trying to use more than one IP address while
only paying for one.  Print out your values and the next time the connection
drops, ask COX the Mac address that is currently connected to your cable
modem.  If it is not one of your macs, then there could be a typo in
their mac database.

   # Known CPE MAC Address (Max 3) Status 1 00 14 bf 0f xx yy Dynamic 2 00
14 bf 1f xx yy Dynamic 3 00 07 40 b5 xx yy Dynamic

Under the cable modem's "Help" page, this is what i have.  Firmware should
be updated by COX automatically.

Software Version: SB5120-2.19.0.10-SCM01-NOSH
Hardware Version: 4
MIB Version: II
GUI Version: 1.0
VxWorks Version: 5.4