Apple products blocked

[changoneman]

Our guest Wi-Fi at work allows internet access for all but it's blocking our outside host server from connecting, but only on apple devices. Says cannot connect on port 491. Works fine on android or windows laptops, any ideas

[MerakiDave]

Not sure I understood, can you clarify, if this is outbound traffic from internal wifi guest clients to an external server, or the external server cannot connect inbound to apple devices on internal wifi?  I'm guessing it's Apple devices on your guest wifi, trying to connect outbound to an external server (your server?) on port 491?  What server/service are guests trying to connect to, assuming this is TCP/491, and how does it work (what do they get) if accessing it from an iPhone over cellular when not on your guest wifi?  Looks like it's for remote windows/unix application interface access.  What is the Internet or perimeter device, a Meraki MX?  Have you tried doing some packet captures on the wired side of the AP, and lining that up with firewall logs, to confirm what is or isn't happening?  Is there a support ticket opened, or just trying here in the community first?  

[changoneman]

Sorry I fail to mention in my email, they connect to application server using app called graphon. Once the app communicates with external server, it prompts for username and pwd. I didn't test cellular directly, but I did use my hotspot on my smartphone which would be the equivalent. This did work as there are no restrictions since its a personal hotspot.

No I didn't use any packet captures, didn't have access to cloud manager. It's just very odd that android would work but not iphone or osx. 

Guess I could have checked with ports were listening on osx as well.

[changoneman]

The model number mr32. I'll check some settings this week, but we no longer have this laptop. Not sure when their visiting again. I'll try another apple device and post back.