Computers with IPV6 installed and MT Hotspot
I had a long standing problem that I've just figured out so I thought I would share with you all.
The problem is that clients with IPV6 installed on their machine could not use my hotspot. They would pull a good IP address from DHCP and could ping IP's all day but when they went to surf they would never get redirected to login and so couldn't use the net. IPV6 was being loaded automatically through windows update and this would periodically "break" several people's computers. I'd say we got at least 2-3 trouble calls per day as a result of this.
The source of the problem is how IPV6 clients do DNS lookups and MT's built in DNS server.
Without IPv6 installed I could ping hotspot.mynetwork.net
But as soon as IPV6 was installed, an attempted ping would result in "Ping request could not find host hotspot.mynetwork.net"
When configuring a hotspot it's common to also configure a DNS name for it for more aesthetic access and to support the use of an SSL certificate for secure logon.
ex. / ip hotspot profile set default dns-name="hotspot.mynetwork.net"
This creates a dynamic entry for the hotspot DNS name in "/ip dns static" and when users go to surf, the MT hotspot will redirect them to that DNS name so they can logon ie. https://hotspot.mynetwork.net/login.cgi
When a a non IPv6 enabled client attempted to logon, they would be redirected to "https://hotspot.mynetwork.net/login.cgi
", do a DNS A name lookup for "hotspot.mynetwork.net", get the resulting IP from the hotspot DNS server, and load the proper page. IPV6 clients do their initial lookup for a AAAA record. The MT DNS server doesn't know how to answer a request for a AAAA record so it passes the request up to it's parent public DNS server. If the DNS name of your hotspot isn't registered in a public DNS server (and normally, why would you want it to be as it's only significant to the local and probably private IP network) then the client will get an "unknown name" response from the DNS server and never be able to resolve the name of the hotspot and so not load the redirect/logon page.
The fix is to create a public DNS entry for your configured hotspot name. It doesn't even need to be accurate. Your client, seeing that the result of the AAAA record lookup is not an an IPv6 address, will follow it up with an A record lookup, which will be properly answered by the MT DNS server.
http://en.wikipedia.org/wiki/IPv6#IPv6_ ... ame_System
I'm running my hotspot on v2.9.6 so this may not apply to newer versions.