Problems setting up DNS, gateway und subnetmask!

[Tamer Higazi]

Hi David, you are right!
with the command
route -n

he shows me successfully the route to the desired gateway you told me. 
But what about the nameservers? And what is IPforwarding? Do I have to 
enable that flag in the options file?

David Hart schrieb:

>On Wed, Dec 28, 2005 at 02:07:02AM +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
>>    
>>
>
>Does your ISP not have a DHCP server to save messing about with manual
>settings?
>
>If they do then go to System -> Administration -> Networking
>and set eth0 to DHCP.
> 
>[snip]
>  
>
>>auto eth0
>>
>>iface eth0 inet static
>>address 81.10.53.22
>>netmask 255.255.255.252
>>    
>>
>
>The netmask above only allows for four addresses one of which is the
>network address (81.10.53.20), another for broadcast (81.10.53.23), your
>IP (81.10.53.22), which means the gateway must be 81.10.53.21.
>
>  
>
>>gateway 10.0.0.138
>>    
>>
>
>That IP is not routeable on the Internet (it's private address space)
>and won't work with your netmask.
>
>Perhaps you should check the addresses you've been given or, as I said
>at the top, use the Networking applet and set it to DHCP.
>
>[snip]
>  
>
>>If I enter the command route:
>>
>>Kernel IP Routentabelle
>>Ziel Router Genmask Flags Metric Ref Use Iface
>>81.10.53.20 * 255.255.255.252 U 0 0 0 eth0
>>
>>If I run explicitly this command to add the gateway to my eth0 interface:
>>
>>
>>sudo route add default gateway 10.0.0.138 eth0
>>
>>I receive this errormessage:
>>SIOCADDRT: Das Netzwerk ist nicht erreichbar (Network unreachable)
>>    
>>
>
>That's because of your netmask and the private IP address of the
>gateway.
>
>  
>