On Dec 16, 2006 at 16:07, Dave Briggs praised the llamas by saying: > On 16/12/06, David Pashley <[EMAIL PROTECTED]> wrote: > > > Run "ip link" > > OK: > > [EMAIL PROTECTED]:~$ ip link > 1: lo: <LOOPBACK,UP,10000> mtu 16436 qdisc noqueue > link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 > 2: eth0: <BROADCAST,MULTICAST,UP,10000> mtu 1500 qdisc pfifo_fast qlen 1000 > link/ether 00:13:d3:cd:a6:fa brd ff:ff:ff:ff:ff:ff > 3: sit0: <NOARP> mtu 1480 qdisc noop > link/sit 0.0.0.0 brd 0.0.0.0 > > > "ip addr show dev eth0" > > The line you're interested in here is the line that starts inet. If you > > don't or it starts 169.254 then you don't have an ip address assigned. > > [EMAIL PROTECTED]:~$ ip addr show dev eth0 > 2: eth0: <BROADCAST,MULTICAST,UP,10000> mtu 1500 qdisc pfifo_fast qlen 1000 > link/ether 00:13:d3:cd:a6:fa brd ff:ff:ff:ff:ff:ff > inet 192.168.1.2/24 brd 192.168.1.255 scope global eth0 > inet6 fe80::213:d3ff:fecd:a6fa/64 scope link > valid_lft forever preferred_lft forever > > > Think that's all ok on the network front. What should I check next? > > Thanks for all this help.
So we've been given an IP address from somewhere. Let's see if they have given us a default route. We can do this by running "ip route" mojo-jojo david% ip route 10.187.182.224/27 dev eth0 proto kernel scope link src 10.187.182.233 default via 10.187.182.225 dev eth0 >From this we can see that our default route is to 10.187.182.225 using eth0 network device. Lets try pinging that: mojo-jojo david% ping 10.187.182.225 PING 10.187.182.225 (10.187.182.225) 56(84) bytes of data. 64 bytes from 10.187.182.225: icmp_seq=1 ttl=64 time=0.317 ms 64 bytes from 10.187.182.225: icmp_seq=2 ttl=64 time=0.291 ms 64 bytes from 10.187.182.225: icmp_seq=3 ttl=64 time=0.224 ms --- 81.187.182.226 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2001ms rtt min/avg/max/mdev = 0.224/0.277/0.317/0.041 ms So we know we can at least reach the router. Now, lets see if we can get any further than this. Lets try pinging Ubuntu's webserver. mojo-jojo david% ping 82.211.81.166 PING 82.211.81.166 (82.211.81.166) 56(84) bytes of data. 64 bytes from 82.211.81.166: icmp_seq=1 ttl=52 time=30.5 ms 64 bytes from 82.211.81.166: icmp_seq=2 ttl=52 time=30.8 ms 64 bytes from 82.211.81.166: icmp_seq=3 ttl=52 time=30.2 ms --- 82.211.81.166 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2006ms rtt min/avg/max/mdev = 30.232/30.532/30.836/0.318 ms If this works, then we have working networking and can move on to checking DNS. If this doesn't work, we need to find out where the problem lies using mtr (I'd normally suggest traceroute here, but it doesn't look like it's a part of the standard Ubuntu install). We will trace the route to ubuntu's webserver again. mojo-jojo david% mtr -r -c 1 82.211.81.166 HOST: mojo-jojo Loss% Snt Last Avg Best Wrst StDev 1. brian.catnip.org.uk 0.0% 1 0.4 0.4 0.4 0.4 0.0 2. 10.187.182.201 0.0% 1 1.1 1.1 1.1 1.1 0.0 3. careless.aaisp.net.uk 0.0% 1 30.2 30.2 30.2 30.2 0.0 4. needless.aaisp.net.uk 0.0% 1 28.7 28.7 28.7 28.7 0.0 5. ge-2-0-216.ipcolo2.London1.L 0.0% 1 30.2 30.2 30.2 30.2 0.0 6. ae-0-55.bbr1.London1.Level3. 0.0% 1 30.2 30.2 30.2 30.2 0.0 7. as-0-0.bbr2.London2.Level3.n 0.0% 1 30.3 30.3 30.3 30.3 0.0 8. ge-3-0-0-55.gar1.London2.Lev 0.0% 1 30.2 30.2 30.2 30.2 0.0 9. 195.50.91.146 0.0% 1 30.4 30.4 30.4 30.4 0.0 10. vlan102.core-l-1.lon2.mnet.n 0.0% 1 29.6 29.6 29.6 29.6 0.0 11. 85.133.32.130 0.0% 1 31.7 31.7 31.7 31.7 0.0 12. 82.211.81.76 0.0% 1 30.0 30.0 30.0 30.0 0.0 13. signey.ubuntu.com 0.0% 1 29.9 29.9 29.9 29.9 0.0 This shows us every router between us and the remote machine. The first line will show your ADSL router. The line after that will be the remote end of your ADSL line. If your adsl is not connected you won't be able to reach the second hop. Anything beyond this is nothing you can control, but considering it works in Windows it's unlikely that this is the case. There is another possibility why you can't reach the second hop and that is that the default route isn't correct, but this address should have been given to you via DHCP like your IP address. If this is all working, we can check DNS. Try looking up a host by name using the host command: mojo-jojo david% host www.ubuntu.com www.ubuntu.com has address 82.211.81.166 If this works, then your networking should be working fine. If not, then we need to check /etc/resolv.conf. It should look something like: mojo-jojo david% cat /etc/resolv.conf nameserver 10.187.182.226 nameserver 10.187.182.229 Here we list DNS name servers. You should edit this file to use the name servers that you were given by your ISP. > -- David Pashley [EMAIL PROTECTED] Nihil curo de ista tua stulta superstitione. -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.kubuntu.org/UKTeam/
