Setting up linux box to forward requests
We use RM for our internet, using SmartCache2 as a proxy.
I have recently set up a new VLAN for our wireless devices on a new ip range (184.108.40.206/21) and want these to bypass the SmartCache2 proxy and connect directly to the internet. We have been trying to use a linux box to do this, but now we're a little stuck.
We have Ubuntu installed with 2 NICS (one on VLAN1, one on VLAN2) - our main HP L2 switch does the routing between these and our DHCP server.
We also have a CISCO firewall that acts as a default gateway to the internet.
I've set up a new firewall rule to allow traffic to pass through 220.127.116.11/21 ip range, and can see that it's working ok, with packets being allowed through.
The problem is that we keep getting "cannot connect to DNS" errors on the client end. We want to use OpenDNS for our BYOD, but even setting the DNS server settings manually on the clients doesn't work. I have set up forwarders on our local DNS server to forward requests from 192.168.3.108 (linux box ip) to OpenDNSs servers but still no luck.
I believe we need to use iptables on the linux box to forward 18.104.22.168/21 traffic to our CISO firewall internet gateway, but not entirely sure.