AutoDiscovery class questions


I want to use the AutoDiscovery class to find instances of my applications which are running on my network.

I have this configuration:
1 mac pro (ip address is 192.168.1.x, received from Ethernet 1)
1 Windows 10 (virtual machine) running on the mac pro (ip address is 10.211.55.x)
1 Windows 10 real computer, connected to Ethernet 2 of the Mac Pro (Internet sharing being activated on the mac pro). It therefore has an address of 192.168.2.x.

The app I’m debugging is on the mac pro. The AutoDiscovery object gets a MemberJoined event for only itself (, performs some messaging I tell it to do and then, surprisingly, I get a MemberLeft event for itself. In the end, I have no member in the list (the other 2 computers never appear).

Is this configuration supported?

I’d expect the physical Windows machine to show up at least. Being that the virtual machine is technically on a different network, probably not.

I’m assuming that your Firewall is running on your Mac with this config (and possibly your Windows box). You’ll have to allow traffic on the port(s) used by autodiscovery.

The subnet mask being for the 192.168.1.x address, I’m assuming the 192.168.2.x address is also on a different network, so it should also not work; correct?

Would it work if I have one AutoDiscovery object per network interface, to see all computers? Or would it confuse the way AutoDiscovery works?

Windows automatically asked me about that (I got the dialog asking if I wanted to allow the port or not); the Mac has no firewall. So it should not be the problem.


You could change your subnet mask to and those two would be able to talk.

I think it’s a good idea, but I’m afraid it’s not that easy. I could change the mask in my home’s router easily, but setting the Mac’s Internet Sharing’s mask is another story. I tried to modify the file, as instructed on the web (just adding the subnet mask); however, even after restarting the Mac, the Windows computer still gets a subnet mask of If I set the mask manually to in the Windows PC (and fill the others data), it can still connect to the Internet, but both computers can’t see each other (even tried with a ping). I’m starting to think it’s not possible to do that.

Hi Greg,

Could we have some examples for Web version and console version for AutoDiscovery ? and the Desktop version updated to the latest XOJO 2019R3 ?