Group Speaker Casting issues from two different local networks

[NCT_JR]

Quick Overview.  I separated my wireless devices to their own network (SSID), example: Security Devices, IoT, Private.   All my Google Speakers are on IoT and my Cellphone is on Private

I have opened all the ports that I can find between IoT and Private for Google Home/Google Smart Speakers.  

(Here is what I found)

Ports that should not be blocked on the network

• Outgoing UDP Multicast on port 1900 and 5353
• Incoming UDP Unicast on arbitrary ports > 53 and 123
• Outgoing HTTP on port 8008, 8009, 80 and 443

I spent the next few weeks testing and adding ports for all devices between IoT and Private.  Finally, I applied the final rule of block all other ports/traffic. (allowing only what is needed) Everything is working as expected, except for multicast to group speakers.

My issue: I can cast to each speaker separately, but not to the group of speakers.  Once I connect my Cellphone to the IoT network (not Private) I can now cast to the group speakers. 

I appear to be missing ports, correct?  Any suggestions? 

[NCT_JR]

Bump? 

[Muddi]

Hey NCT_JR,

Thanks for sharing details about the issue here. My apologies for the delays.

I know how challenging it is when you're having issues casting on an audio group. You might want to check the DNS settings on your router and make sure it is set to 8.8.8.8 and 8.8.4.4, as these are Google public DNS addresses.

Hope this helps.

Cheers,

Muddi

[NCT_JR]

That did not help, as I already have Googles DNS configured. 

[Muddi]

Hi NCT_JR,

Got it! Those are just the settings that we can provide because Google Home/Nest devices don't really need special network settings to work. You might want to check with your network provider if they can suggest some ports that you can use.

Cheers,

Muddi

[NCT_JR]

Which ports are needed?  There is clearly a network issue, when devices are on separate sub nets.  Keep in mind that all other Google Home/Nest devices appear to be working in this "mixed" environment.... After opening ports.   (every product/device listed below has a dedicated port that they use and I have created firewall rules for all of them)  

In reference to my original post. 

IoT Network = 192.168.4.x  (Smart Speakers, TV, Chromecast, Stadia, PS5, HD Homerun, etc)

Private Network = 192.168.2.x  (Cellphones, Tablets, PC, Servers, etc)

Security Network = 192.168.3.x  (Nest Cams, Thermostats, Nest Doorbell, Door locks, Smoke detectors, etc) 

[Muddi]

Hi NCT_JR,

We'd be happy to take a look into this for you. .Please fill out this form with all the needed information then let me know once done.

Cheers,

Muddi

[NCT_JR]

Just completed the form

[Muddi]

Hi NCT_JR,

We got the form you've submitted. We'll be reaching out to you via email and let's continue working on your concern through that channel.

Cheers,

Muddi