External network routing table configuration

If you cannot connet to external network, you may try below routing table configuration.

route add default gw 172.22.31.127
route add default gw 172.22.31.254
route add -net 172.0.0.0 netmask 255.0.0.0 gw 172.22.31.254 dev eth0
route add -net 207.0.0.0 netmask 255.0.0.0 gw 172.22.31.254 dev eth0