Did you also whitelist all the needed DNS servers? When on untrusted networks, I usually run the bind DNS server on my laptop (querying directly the root servers) so it can validate the records using DNSSEC.
Posted Aug 31, 2011 18:03 UTC (Wed) by raven667 (subscriber, #5198)
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No, the only dns servers allowed through the captive portal prior to authentication are the recursive ones we maintain, these are what are suggested via DHCP. I imagine your config would break on a lot of captive portals unless they had blanket rules allowing any dns traffic.