We have recently decided to enable WLAN for guest users that authenticates users by redirection to WLC's virtual address (220.127.116.11).
I have created WLAN and assigned management interface for it on WLC.
Interface points to dhcp server that resides on the same segment and issues all "guest" clients with ip addresses which works fine.
The problem is with web authentication redirection when using names (eg: http://www.cisco.com).
Clients are supposed to be redirected to web auth. page once supplied with relevant dhcp information.
Redirection occurs when client opens up internet browser (eg. IE).
Unfortunately this does not occur when browsing to URL's using names.
When browsing to an ip address, redirection to 18.104.22.168 works just fine.
I have applied preauth acl for guest WLAN to allow DNS traffic, but that didn't help.
I have noticed that when ACL is applied clients can resolve dns for about 5 seconds and after that everythings stops.
I tried to allow icmp - just to prove the concept and noticed that after 6 - 10 packets connection drops.
my WLC is running 4.0.179 firmware
One more thing, when I access web auth page by going to http://22.214.171.124 and authenticate succesfully i am able to browse the internet which indicates that DNS resolution works fine.
Please help i am out of ideas.