macOS Firewall and Bonjour

[barenature]

Hello,

I have developed a Mac app that communicates with the iPad through Bonjour. One my customers, however, experiences problems with connecting both devices. It is difficult to remedy this through email.

I was wondering if the Bonjour service could be disrupted by his firewall. He tells me that the Mac app is accepting incoming connections, but that both devices can't find one another on the network (same network).

Do you have any suggestions or recommendations? How would you tackle such an issue (this is the first occurrence of this issue and I cannot replicate it myself).

Thanks!

 

[xStep]

Well, a firewall controls ports. If those ports are not explicitly opened and allows the IP addresses through, then yes, the firewall could be disallowing the communication. Ditto if the ports have some other control applied to them. I'm simplifying I'm sure.

If you allowed Bonjour to randomly pick a port, then without allowing all traffic through the firewall, there isn't much you can do via WiFi. If your app has the ability to set a fixed port number, then do that and ask the customer to open that port up in the firewall.

Another thing you might try is to use Bluetooth. Bonjour also advertises over bluetooth. Try this at your location first. Turn on bluetooth on both the iPad and Mac and for completeness, turn off WiFi on both devices. Now try the communication. I know this works with two iPods, but I'm not sure if it will work with a Mac. I think Apple has placed some limits on iOS devices regard BT. Also note that it is slower than WiFi and isn't as friendly to exchanging large chunks of data. It may also be slower to make the initial connection.