Ubuntu 12.04 Server installation - no network

[aaron27]

I have just installed a new 12.04 machine and I cannot get the commands
sudo apt-get update or
sudo apt-get install gnome to work, they are not connecting.

I have set this machine a static IP. I have modified the /etc/network/interfaces file to show as below:



auto eth0
iface eth0 inet static
address – static ip
netmask 255.255.0.0
gateway gateway ip
dns-nameservers dns server ip's


I can confirm the two DNS entries show in /etc/resolv.conf

Previously this has worked fine but I am not sure what I have done wrong (or missed) in this instance

[TheFu]

Post the complete /etc/network/interfaces file.

Also... http://blog.jdpfu.com/2013/03/01/linux-troubleshooting-101-networking

[aaron27]

#This file describes the network interfaces available on your system
#and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static
address 'ip address'
netmask 255.255.0.0
gateway 'gateway ip'
dns-nameservers 'dns ip' 'dns ip 2'



On that link. Pinging router, server, known internet ip all come back unreachable. pinging google gives me a message saying unknown host.

resolv.conf shows the two same DNS entries from the interfaces file.

Route shows the below:





Destination Gateway Genmask Flags Metric Ref Use iface
default 'gateway ip' 0.0.0.0 UG 100 0 0 eth0
localnet * 255.255.0.0 U 0 0 0 eth0




Not sure how much this helps?

[TheFu]

That is not a valid interfaces file. Here's one of mine.

auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static
address 172.22.22.13
gateway 172.22.22.1
netmask 255.255.255.0
# mtu 1500
dns-nameservers 172.22.22.1

Real IPs are needed. There isn't any replacement template engine for this stuff in that file.

[aaron27]

I do have IP's in my actual interface file I just dont wish them to be in the public domain.
My Interfaces file looks the same as yours.

I have been googling this issue and came across an instruction to run the command


arp -a

This then shows my two DNS IP addresses as incomplete on Eth0



:~$ arp -a
? (172.16.10.1) at <incomplete> on eth0
? (172.16.10.14) at <incomplete> on eth0


I know both the DNS IP addresses work as I use them on my personal PC.