.local tld name resolution

It's not the phone, it's your ad setup. No one should use .local for anything other than zeroconf devices. You should be using a real, valid fqdn.

Message was edited by: GrahamGilbert

This seems to be general DNS host name resolution problem. On my iPhone4 on iOS 4.0.2 Mobile Safari will not connect to any webservers within the local LAN when addressed with their <hostname>.local name. (It does however connect fine when using the private IP address of the webserver).

The correct DNS server any search domain are being set via DHCP.

As aside: My iPad does not have any problems resolving the hostnames within the same WiFi network.

It is not a problem with your phone, rather a problem with the way your DNS is set up. .local names will never resolve if you are on the public Internet, they are not supposed to (that is why it is called ".local"). You will need to use a nameserver that includes your version of .local. Either that or fix your DNS so you don't use .local, which is much better.

Sorry, but it is NOT a problem with my DNS setup; it is a behavior only the iPhone exhibits. As I already stated, everything is set up correctly (the DNS server lives within the same LAN and surely knows about the .local tld and the associated hosts). Other devices including, but not limited to an iPad and a MacBook Pro, work flawlessly with the same DHCP based setup.

See also this thread http://discussions.apple.com/message.jspa?messageID=8665296 for prior observations by other users of similar problems.

The iPhone will resolve .local names just fine, as long as it is using a name server that serves up the .local zone correctly. Earlier versions of iOS that was not necessarily the case. There also was a DNS problem when using a VPN, but both have been fixed. You need to take a diagnostic look at your DNS log files to see if the iPhone is in fact, using the name servers you think it is. It really does work if set up correctly.

The thread from 2008 you referenced was in the general timeframe when DNS was flaky on the iPhone. But all has been been fixed since.

OTOH, there really is no need to use .local anyway, but that is a DNS discussion way beyond the scope of this forum.

I will see if I can get a trace of the network communication.

On the other hand, a more recent thread (this summer) http://discussions.apple.com/thread.jspa?threadID=2502568 also references DNS problems specifically with iOS4 and .local tlds.

I did a network traffic trace for in- and outbound traffic of the iPhone4. Here is what I saw:

* When I initiate a Google search in Mobile Safari, the local DNS server receives a standard A record query for www.l.google.com -> everything works fine.
* When I try to open http://media.local (local webserver), the iPhone will issue a MDNS query to 224.0.0.251 instead of contacting the configured DNS server. The A record query is repeated a couple of times with media.local, then media.local.local is tried a couple of times (as local is configured as search domain). -> Finally Safari gives up and says, the host could not be found.

In essence the iPhone4 does NOT query the configured DNS server for .local tlds and thus cannot resolve these host names.

To my very best knowledge, I do consider this a bug.

Here's a little recap of the findings so far:

- iOS4's DNS name resolution for .local top level domains does not currently (4.0.2) work properly

- the issue has come up before (~2008) but has apparently been fixed in iOS 3.something, so it looks like a regression bug -- I can personally confirm that iOS 3.2.x does not have this problem

- root cause: according to a network trace iOS4 will not contact the configured DNS server but instead go for MDNS lookup via 224.0.0.251 to resolve .local tlds and is thus unable to resolve .local hostnames if no MDNS response is received

It looks like we are facing a regression bug in iOS4. What would be the appropriate next step(s)? Can this be confirmed by others? What would be the proper procedure to file this as a bug so we can hope to get it fixed at some point?

FYI: The problem went away with the iOS 4.0.2 update. So everyone on 4.0 or 4.0.1 should update (which is a no-brainer, of course).

Thx

Martin Rehfeld wrote:
FYI: The problem went away with the iOS 4.0.2 update.

That was supposed to read "iOS 4.1 update" ! Sorry for any confusion.