Hi guys,
I have a Cisco 2600 series router and I'm not 100% sure which ports I need to allow through my firewall for domain name resolution. When the firewall is down the router resolves ip's fine. But when the firewall is up it doesn't. I am permitting UDP and TCP packets on port 53 to go through but it still won't resolve ip's to domain names.
My ACL is defined as follows:
access-list 101 permit tcp any any eq 53
access-list 101 permit udp any any eq 53
Am I missing a port that is needed? I'm sure this is something simple. Your help is greatly appreciated.
Niall