Comment 5 for bug 83715

This happens on Fiesty release too. At home, I have no wired network connected; I use GnomePPP to dial in to the ISP.
Updated to repositories on 2007-05-14. Kernel 2.6.20-15-generic.

Immediately after startup::

xxxx$ ping localhost
connect: Network is unreachable

xxxx$ ifconfig
eth1 Link encap:Ethernet HWaddr 00:15:C5:00:01:5A
          UP BROADCAST MULTICAST MTU:1500 Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
          Interrupt:18

There is no 'lo' interface.

This causes all sorts of problems (startup delays, slow application launch, slow response to power button and panel Quit applet, Evince and EOG not printing, etc...)

xxxx$ sudo ifup lo
ifup: interface lo already configured

This is strange, ifconfig did not see 'lo'

xxxx$ sudo ifdown lo
xxxx$ sudo ifup lo
xxxx$ ping localhost
PING localhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.033 ms

After this, power button works properly, Evince and EOG print properly, etc.

/etc/hosts, /etc/network/interfaces seem to be correct:

xxxx$ cat /etc/hosts
127.0.0.1 localhost xxxx
127.0.1.1 xxxx

# The following lines are desirable for IPv6 capable hosts
#::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts

xxxx$ cat /etc/network/interfaces
# 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

#iface eth0 inet static
#address 172.25.143.31
#netmask 255.255.0.0
#gateway 172.25.161.1

#auto eth0

#iface eth1 inet dhcp

#auto eth1

So everything seems to be set up properly, but it appears that nothing calls /etc/init.d/loopback

Any ideas?