[AuckLUG] ADSL

[David Hawke]

editor at inventory.co.nz wrote:
> I tried "ifconfig -a" but didn't really understand what I was 
> looking at.
>
>   
OK

ifconfig -a lists the status of all of the network connections

lo is the localhost network connection with an ip address of 127.0.0.1

eth0 is the first of the ethernet connections and will have an ip
address of 192.168.1.x where x is in the range of 1 to 254, given your
settings (note that this can take many other values but I've simplified
to your network)

Each PC on the network has a separate IP address (for obvious reasons)

One of my PC's has this as a response to ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:E0:4C:30:DD:B7
          inet addr:10.168.0.247  Bcast:10.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::2e0:4cff:fe30:ddb7/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:96917 errors:7 dropped:36 overruns:7 frame:0
          TX packets:79155 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:72995750 (69.6 Mb)  TX bytes:10565593 (10.0 Mb)
          Interrupt:16 Base address:0xc000

The important line is the inet addr line - with inet addr and mask being
the key bits (again, over simplified a bit)
> On one computer, I found that changing the last number of the IP 
> address to a single digit dealt with the problem and I can now 
> access the Internet on that computer.
>   

OK - if you change those values, steer away from anything already assigend
- 192.168.1.1 - your gateway
- any other values assigned to other PC's
Keep the last digit in the range 1 to 254 - eg 192.168.1.100 is probably
safe
> On the other computer, after making a similar change, I managed to 
> ping the gateway but not a DNS. Now I can't even start a terminal 
> session or launch any applications when running Ubuntu on that 
> computer. However, I intend to reinstall the operating systems on 
> that computer so, hopefully, all will be well.
>   
I'd suggest rebooting first which will reset all of the values

In principle, if you have a DHCP server running on your gateway box, you
should automatically get all of the appropriate settings.

Hang in there :-)

David H
> Thanks for your help.
>
>