[SOLVED] Network down after reboot

[francoisbuntu]

I booted my computer yesterday only to find that network was not working any more. Multiple reboots didn't improve things but network was fine on my windows partition and other lucid lynx partition.
Playing around with ifconfig showed eth0 was down. I managed to set an IP and a gateway with ifconfig but I still can't access the internet properly behind my livebox modem router. I can however ping websites and the local network seems fine (also other computer on the network has no problem accessing the net).

It looks like something that happened automatically at boot before doesn't work anymore. Ideally I'm looking for some sort of procedure to get everything back to how it was before without any need for manual intervention or alternatively for some commands of the ifconfig sort that I could put inside a script.

[dibl]

Re: Network down after reboot

I would advise starting with Detonate's excellent guidance here: http://kubuntuforums.net/forums/inde...opic=3100052.0

[francoisbuntu]

Re: Network down after reboot

Big thanks.
The procedure didn't actually work out for me. After modifying and saving interfaces as indicated nothing happens. Also my original /etc/networks/interfaces file contained only the 2 lines:

auto lo
iface lo inet loopback

And that was the same as on my other working lucid install.

What did help me out though was the reference to the resolv.conf file which was actually the missing piece for me. I added the address of my router in there and things are now working.

Here is a recap of the steps for me:
1. sudo ifconfig eth0 up 192.168.1.30
2. sudo route add default gw 192.168.1.1
3. edit resolv.conf adding the line:
nameserver 192.168.1.1

At this point I'm still going to have to go through steps 1 & 2 each time I reboot though and I'm not entirely sure this is a clean solution. So still looking for the right way to do it.

[dibl]

Re: Network down after reboot

Is it not possible, or desirable, to set your router to be a DHCP server? That makes the IP addressing of network nodes happen automatically.

If not, then you are stuck making a static network (each machine gets its IP address permanently saved in its configuration).

[francoisbuntu]

Re: Network down after reboot

My router does function as a DHCP server but I don't know how to make that happen again.
Something broke and the only way I was able to solve it was by using a static IP. My network knowledge is very basic.

[oshunluvr]

Re: Network down after reboot

By "That procedure didn't work for me..." are we to assume you removed knetwork-manager as suggested? If so, start by editing you /etc/network/interfaces and add your ethernet port to it:

# The primary network interface
auto eth0
iface eth0 inet dhcp

should bring up eth0 and use dhcp. If you want static IP then use

# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.1.30
gateway 192.168.1.1
netmask 255.255.255.0

BTW: Rebooting is not required to active these changes, just type this in a terminal:

sudo service networking restart

[francoisbuntu]

Re: Network down after reboot

I did remove knetwork-manager.
I tried your suggestion of typing sudo service network restart, unfortunately I get:
network: unrecognized service

[oshunluvr]

Re: Network down after reboot

Oops

networking

[francoisbuntu]

Re: Network down after reboot

Lots of thanks! It works fine on reboot now.