You didn't say how you were accessing the linux system via the phone. 
I'm assuming that you are trying to connect via ppp (or slip) and are
attempting to access the internet through this tcp/ip connection.

The problem here is that your ISP (at the other end of the DSL link) is
only expecting to receive packets addressed to the ip address of your
Linux machine.  Your remote (via the modem) machine also has an ip
address.  Your Linux machine knows how to route network packets to your
remote machine and to the internet via your DSL.  Unfortunately, the ISP
does not know to route packets from the internet to your remote machines
ip address.

You have two options:

1) Pay your ISP for additional ip addresses.  This usually puts you in a
business class account and you pay additional bucks.

2) You can set up your Linux machine to do masquerading.  This means
that when Linux receives packets from your remote, it will change the
source ip address/port number of that packet to the ip address of your
Linux machine and then sends it on to the internet.  When the response
comes back from the internet, it replaces the ip address with the one to
your remote PC and off it goes.

There are several how-tos on setting up masquerading.  If you need more
information come on back and I or one of the other Linuxites can help.

Hope this helps.

info at hjcomps.com wrote:
> 
> I'm new to your mailing list and as of now I have no particular linux
> questions.  However, I'm trying to get my dialup modem to work so that I
> can dial into my Red Hat box which is connected via DSL.  I can dial in and
> get connected but can't access the Internet fully.  Maybe someone else in
> your group has attempted this before and I can direct my questions to that
> person.
> 
> The second reason for this email is I own a building with 6 one room
> offices 5 block from a swimming beach in White Bear Lake (including a
> shower for after your swim).  If the group would like to hold a meeting
> their I would be open to the idea.  One of the office rooms can hold 24
> people or more.  The cost would be minimal (or free).  If any would like to
> start some type of business or move their business (preferably a linux
> bases business) to the area I would be open to suggestions.  It does have a
> nice storefront.
> 
> Thanks for your time.
> Hank Axt
> 612.750.5330
> axt at hjcomps.com
> 
> _______________________________________________
> Twin Cities Linux Users Group Mailing List - Minneapolis/St. Paul, Minnesota
> http://www.mn-linux.org
> tclug-list at mn-linux.org
> https://mailman.mn-linux.org/mailman/listinfo/tclug-list

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