Comcast Static IP Changed With New Modem?

Rafael Possamai rafael at gav.ufsc.br
Wed Feb 11 18:27:36 UTC 2015


I've had a similar mistake happen with TWC. It's most likely a glitch in
their config system which should use the gateway's mac address in order to
assign a static IP on the docsis modem. Tech support should figure this out
pretty quick without escalating it much further. I've had an instance where
a second line/modem was added with the same gateway IP, and that brought us
down for over a day until they got around to fixing it.

My suggestions is to always keep your gateways/edges monitored with a
service like Monitis. I use ping monitors every single minute from three
different locations in the US (abroad available too) and get email/SMS/call
whenever something fails once, twice, etc from one, two or more locations.
Really cool monitoring system.

Hope this helps.



On Mon, Feb 9, 2015 at 10:32 AM, Justin Krejci <JKrejci at usinternet.com>
wrote:

> Has anyone run into the situation where their static IP address from
> Comcast (on the business class cable modem Internet service) was changed
> when the modem was replaced?
>
> We have a remote site that uses Comcast as a backup Internet connection
> and when we went to use it recently our VPN tunnel would not establish.
> After working with the Comcast support group we discovered Comcast changed
> our static IP address. I am working through trying to figure out the when
> and the why with Comcast still and suspect it was changed when the modem
> was replaced back in December. The modem was replaced by Comcast as our
> previous modem was apparently EOL'ed.
>
> We're now setting up additional monitoring to verify the accessibility of
> our remote site via the Comcast connection so we don't have any future
> uh-ohs when we need to use our backup connection and it too is not fully
> functional.
>
> TIA,
> -Justin
>



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