Why can't I access localhost without an internet connection?

Question

For some reason I cannot access localhost without an internet connection in Ubuntu.

As soon as I disconnect from the internet (with the networkmanager GUI), both ping localhost and ping 127.0.0.1 return:

ping: sendmsg: Operation not permitted

I switched off iptables, iptables -L gives:

Chain INPUT (policy ACCEPT)

target prot opt source destination

Chain FORWARD (policy ACCEPT)

target prot opt source destination

Chain OUTPUT (policy ACCEPT)

target prot opt source destination

What could be the problem?

Answer 1

Run the command:

sudo ipmasq

Try to ping localhost and hopefully it should work.