After running apt-get upgrade and restarting an Ubuntu Server install I noticed the computer didn't have a network connection.

I checked ifconfig

~$ ifconfig

lo        Link encap:Local Loopback

          inet addr:127.0.0.1  Mask:255.0.0.0

          inet6 addr: ::1/128 Scope:Host

          UP LOOPBACK RUNNING  MTU:65536  Metric:1

          RX packets:7376 errors:0 dropped:0 overruns:0 frame:0

          TX packets:7376 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:0

          RX bytes:1424 (1.4 KB)  TX bytes:1424 (1.4 KB)

The interface 'em1' was missing :/

So I tried ifconfig em1 up which brought the interface up and then dhclient em1 to get an IP address, but I ran into this error:

~$ dhclient em1

dhclient: error while loading shared libraries: libc.so.6: failed to map segment from shared object: Permission denied

~$ dhclient

dhclient: error while loading shared libraries: libc.so.6: failed to map segment from shared object: Permission denied

Does anyone have any idea what could be wrong? A number of people seemed to have issues with SELinux blocking dhclient, but even with setenforce 0 I get this issue.

I've used dhclient to manually bring up an interface on this computer before so I'm not sure what suddenly changed (and what changed to stop the interfacing auto-setting up on startup).

EDIT: The network adapter is fine and everything works when the ip/route/nameservers are set manually

Reinstalling isc-dhcp-client and isc-dhcp-common didn't help, nor did reinstalling libc6

EDIT2: I tried gertvdijk's suggestions. My /etc/network/interfaces is:

auto lo  

iface lo inet loopback  



allow-hotplug em1  

iface em1 inet dhcp  

I tried sudo ifup em1 but I get the same error :(

~$ sudo ifup em1

dhclient: error while loading shared libraries: libc.so.6: failed to map segment from shared object: Permission denied  

Failed to bring up em1.