Problems setting up DNS, gateway und subnetmask!

[David Hart]

On Wed, Dec 28, 2005 at 11:47:31AM +0100, Henk Koster wrote:
> On Wed, 28 Dec 2005 02:07:02 +0200, Tamer Higazi wrote:
> 
> > Hi!
> > I have received from my ISP an IP, DNS, Subnetmask and the DNS 
> > Serverentries to add to my ubuntu linux machine
> 
> Whoa! This is where you are wrong already -- these data are for your 
> ADSL router; your Ubuntu Linux machine is on the inside 10.0.0.0/24 LAN.

You might well be right of course but, how do you know he's using an
ADSL router?

I was using an ADSL router/modem until a week ago which works as you
describe (I've since lent it to a friend).  Right at this moment,
while I'm reorganising my flat, I'm using my ADSL _modem_ plugged
into my laptop's built-in eth0 interface which puts my real Internet
address on that interface.  I'm routing the rest of my network to
the Internet through the laptop's wireless interface on eth1.

  david at box:~ $ ifconfig
  eth0      Link encap:Ethernet  HWaddr 00:90:F5:1E:07:5C
            inet addr:82.69.92.65  Bcast:82.69.92.255  Mask:255.255.255.0
            inet6 addr: fe80::290:f5ff:fe1e:75c/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:724959 errors:0 dropped:0 overruns:0 frame:0
            TX packets:379935 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000
            RX bytes:481363219 (459.0 MiB)  TX bytes:42659600 (40.6 MiB)
            Interrupt:9 Base address:0x4000
  
  eth1      Link encap:Ethernet  HWaddr 00:09:5B:C4:00:03
            inet addr:192.168.98.100  Bcast:192.168.98.255 Mask:255.255.255.0
            inet6 addr: fe80::209:5bff:fec4:3/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:468407 errors:0 dropped:0 overruns:0 frame:0
            TX packets:386934 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000
            RX bytes:160497773 (153.0 MiB)  TX bytes:330581468 (315.2 MiB)

  david at box:~ $ route -n
  Kernel IP routing table
  Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
  192.168.98.0    0.0.0.0         255.255.255.0   U     0      0        0 eth1
  82.69.92.0      0.0.0.0         255.255.255.0   U     0      0        0 eth0
  0.0.0.0         82.69.92.66     0.0.0.0         UG    0      0        0 eth0

[snip]
> > auto eth0
> > 
> > iface eth0 inet static
> > address 81.10.53.22
> > netmask 255.255.255.252
> > gateway 10.0.0.138
> > dns-search lan
> > dns-nameservers 163.121.128.134 212.103.160.18
> 
> This is a mix of LAN and Internet... no wonder it doesn't work.
> I recommend you change it to 
> 
> auto eth0
> iface eth0 inet dhcp

That's what I suggested and the simplest thing to try first.
 
> The router is also the nameserver for the LAN, so make sure that
> /etc/resolv.conf reads as follows:
> 
> search lan
> nameserver 10.0.0.138

That step will be unnecessary if they are assigned automatically by
DHCP.
 
> With these settings you have a route from your Linux machine to the LAN,
> so next login with your browser to the router at http://10.0.0.138. You
> must configure the router with the information given:
[snip settings]

There's no must about it AFAICS.  The router/modem (if indeed, that is what
it is) could very well pick its own settings up from DHCP.  That is what
I would try first.

And don't you think it's a bit of an odd address for a router?  That's
what makes me think it's not that but a typo.
 
-- 
David Hart <ubuntu at tonix.org>