I'm using a 3G modem whilst o2 tranfer over adsl. trouble is no websites load but I can resolve domains. I enabled masquerade on the PPP0 ( modem) interface. added the server as default route for all workstations.
iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE
net.ipv4.ip_forward = 1″ to /etc/sysctl.conf