Since this last week-end, I try to install my server on Linux Fedora Core 3, and after lots of problem whose I have been independant off, there is still some one :S
Actually, I work for my thomson speedtouch 330 ADSL to work ... After some usual steps, I have finally found the needed micro code and firmware, and the "modem_run", then "pppoa3" commands are errorless and all is ALMOST fine ...
Actually, the ifconfig call gives well all the information about, between other, the ppp0 interface, and the route comand seems to give what is needed (gateway ...);

BUT, althought this I have no access to the net ... with no error into log, neither on the command line ... I am astonished, and very tired at this moment. I would appreciate some help ...

you probably have your dns set up wrong. If your interfaces are up and you can ping locations but cant browse its a dns problem. I forget how I fixed this in my case because it has been so long since I used this modem but I think that will give you an idea on where to start looking for information towards a solution.

Thanks for your help; in fact it is what I think, but I have not been able to get my server worked yet :@
Can you show me your /etc/resolv.conf plz to have an idea of what has to be put into the dns file ???

Well, unforturnatly I am home for the holidays and only have access to my parents windows laptop :x.

I recall needing to put 'usepeerdns' in some file called options or something. Then it will automagically find your isp dns servers. Sorry I cant remember more.

Here is my /etc/resolv.conf:
search maisel.enst-bretagne.fr
nameserver 172.16.23.2
nameserver 172.16.23.1

The nameservers are provided by your ISP, the search entries are usefull only if you are part of a larger network (to use urls like somemachine instead of somemachine.somenetwork.org).

resolv.conf will be different for every isp. If you put this usepeerdns thing in your /etc/ppp/options (i think, really have no idea), it will create it for you.

Thanks to all for your help ...
I have just read your post after having finally SUCCESSFULLY connecting the server on LInux with net access Pffffffffffff !
As we all thought, it was effectively a DNS problem, in fact my resolv.cong syntax was wrong :S bue things are ok now ...
I will just create a personnal DNS server to be wholly independant, using named ... But I have no time for now ...