Unable to automatically determine the external interface

[paromarc]

Hi,

Any idea why I am getting the message "Unable to automatically determine the external interface" ?
I have tried to specify "eth0" but still getting the same message.
root@56dcb3fdb77c:/opt/app/cvpn/cvpn# ./cvpn server vpn.key 192.168.1.176 1956 eth0
Command [ip route show default 2>/dev/null|awk '/default/{print $3}'] failed]
Command [ip route show default 2>/dev/null|awk '/default/{print $5}'] failed]
Unable to automatically determine the external interface
root@56dcb3fdb77c:/opt/app/cvpn/cvpn#