Re: [HSI] How to not make friends with DNS

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NormanS
Premium,MVM
join:2001-02-14
San Jose, CA

·Pacific Bell - SBC

reply to koma3504
Re: [HSI] How to not make friends with DNS

said by koma3504

:

Well if you botherd to notice unless opendns or what ever dns you want to use is hard coded int the modem its 50/50 what dns you will be using at anyone time.

Your basic cable modem is just a bridge, and there is no call to the modem for DNS. That is done in the router, or on the computer.

If you have a combo modem (router+modem), I would expect it to be configurable.

I know this from watching my iftop on my smoothwall box.

there is a way to make a patch to force smoothwall to insist on what ever dns you want.

Not sure what you are looking at, but the behavior doesn't sound like a normal cable modem to router setup.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum

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· 2009-06-07 11:23:58 ·

koma3504
Advocate
Premium
join:2004-06-22
North Richland Hills, TX

1 edit

Here you go i made a screen shot for you.

This is one of charter dns servers.
vip01ftwotx.ftwo.tx.charter.com

the 10.89 ips are peoples modem ip address.

as you can see it is hit and mis i have a open dns entry as well as the charter dns so there far its 50/50.

open dns is hard coded in my smoothwall config in every router and or computer behind it.

And on a bridged CBN modem Yes you can have dns hard codded in the modem itself which would resolve the issue.

Im also being nailed from this ip

68.114.37.166 (68-114-37-166.static.stls.mo.charter.com)

10:47:58 eth0 » - UDP 68.114.37.166 67(BOOTPS) xx.xx.xx.xx 68(BOOTPC)
--
† Koma †
If YOu Don't Think It's Possable!! It's Acually A Reality!!The best way to predict the future is to invent it. Alan Kay!!
Ya Don't Know The signal Till Ya Ride It!!
Voice Break's There's Trouble!!!!

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· 2009-06-07 12:17:21 ·

ImpetusEra

join:2004-05-19
00000

I assume you have DHCP addressing from Charter and not static? Whatever you have connected to the modem whether it be the smoothwall or your router receives the Charter DNS server addresses by DHCP. You'll have to look deeper in your configs to see if there is an option to override that and specify a DNS server on that interface. Most likely the reason you are seeing a connection being made in the smoothwall log is the device receiving an address from the modem is making a DNS request for a NTP server. Everything else in your network receiving the hardcoded opendns by way of DHCP or static assignment is using opendns and never that Charter DNS server. It has nothing to do with coding an address in the modem as you can't.

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· 2009-06-07 13:17:19 ·


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