The portal pass dns enable command enables a device to allow DNS packets to pass through during Portal authentication.
The undo portal pass dns enable command restores the default configuration.
By default, a device does not allow DNS packets to pass through during Portal authentication.
If you use a domain name to access the network, run the portal pass dns enable command to allow DNS packets destined for the DNS server to pass through. However, after this command is executed, all DNS packets are permitted.
You are recommended to run the free-rule command to configure the IP address of the DNS server as the source accessible to users without authentication.