Chromecast 4.0 can't connect to wifi WPA2/WPA3 mixed

[olekstomek]

The same problem as here.

I connected Chromecast 4.0 to my WPA2/WPA3 (mixed) network. After updating, my device cannot connect to the same network. Why?
I have a mix mode (WPA2 and WPA3). If any the device cannot connect to WPA3, it connects via WPA2.
Anyone have a similar problem?

[djtetei]

Chromecast with Google TV does not have support for WPA 3 and is not configured to work in business security networks.

Also check your router AP isolation (should be off) and PMF (should be optional) settings.

[ReubenFarrelly]

WPA3 is nothing to do with business security.  It is the successor to WPA2.

If the Chromecast cannot connect to WPA2 in a mixed mode WPA2/WPA3 network then there is a bug present that the Chromecast developers need to fix.  In a mixed mode network a device not supporting WPA3 can still connect using WPA2 (as should be happening here).

[djtetei]

I made the remark about business security networks because we don't know what other settings @olekstomek  may have on his router.

Also, not all devices have the ability to connect in WPA mixed mode.

[olekstomek]

I believe the problem is with the Chromecast. I use open source software - OpenWrt on the router. I have devices on the network that do not support WPA3 (Xiaomi and Gosund bulbs, Xiaomi and Gosund sockets), but these devices connect via WPA2. The test I did:
1. I only changed my WiFi network encryption from mixed WPA2/WPA3 to WPA2 only.
2. The Chromecast is connected to my network - this is proof that I have no other blockages. This is my private home network.
3. I changed back to mixed WPA2/WPA3, my bulbs and sockets I mentioned connected automatically. Chromecast requires a password for my network - after all, it was already connected to this network over WPA2 so why?

Additionally, Chromecast connected to my WPA2/WPA3 network in the beginning, lost this network after software update.

[Jeran]

Hey there olekstomek,

This is an interesting issue. I talked with a higher tier of support about this issue, and it is stated that our Chromecast devices only support WEP, WPA, and/or WPA2

Honestly, we cannot really say why you were able to connect previously with WPA3. The feature you were able to use before is not supported.

I'm sorry we couldn't have been more help, but if you have any other questions or concerns for me, please let me know.

Best regards,
Jeran

[ReubenFarrelly]

@Jeran Mixed Mode as the OP was using, means both WPA2 and WPA3 capabilities are advertised out of the Access Point.  It means that both WPA2 and WPA3 clients are able to connect to the SSID.  Those clients which support WPA3 will use it, those which do not support WPA3 can still pick up on and connect using legacy WPA2.

So it therefore isn't relevant if the Chromecast supports WPA3 or not.  In Mixed Mode, the Chromecast should be able to connect using WPA2 as it always has.  A well behaved wireless client will ignore capabilities and beacons that it does not understand (like in this case, the Chromecast should be ignoring WPA3).

If it does not connect to a Mixed Mode radio then this is almost certainly a bug in the Chromecast firmware.  I have seen devices before which when they see a capability they do not support, they die or just refuse to connect at all.  That is bad client behaviour and should be fixed and that seems to be what the Chromecast is doing here.  Of course if the Access Point has a poor implementation of Mixed Mode then that could also be a cause.  But wireless clients are notorious for this sort of behaviour.
I would like to see this investigated further.  My two Chromecasts are wired in at the moment but I'll see if I can get one out and test it.  If I can generate captures and/or logs to illustrate the problem where can they be sent to?

[olekstomek]

Hi @Jeran, to be more precise - I wasn't connecting to WPA3.  Network has mixed mode (WPA2 and WPA3), so if Chromecast can't understand WPA3 then WPA2 is available in this network.

I agree with what wrote @ReubenFarrelly. 

[Jeran]

Hey there olekstomek,

I am real sorry about the late response on this, but I've been talking with the engineering team on this issue, and they haven't heard much about this problem with the Chromecast with Google TV models in particular. If the issue is only occurring with a Chromecast Ultra, there has been a recent firmware issue where you need to configure your router to a lower-end 5GHz channel, within the 36-140 range, to get some Chromecast devices connected to a 5GHz band, which may affect this WPA2/WPA3 mixed network as well.   

However, if this issue is occurring on Chromecast with Google TV devices as well, would you be able to submit feedback via the Google Home app with logs enabled so that the engineering team can look into this issue further?

I look forward to your response!

Best regards,

Jeran

[olekstomek]

Thanks for your interest and reply.
I only connect via the 2.4 GHz network (TP-Link 3420 v5 without 5GHz).
I will repeat the steps and send logs for analysis, let you know here that I did it.
However, I will probably do it in the new year because I am currently away from home and cannot access the device. Best wishes by the way!

[totalizator]

Same here. My Chromecast 4 can't connect to WiFi (2.4 &5) anymore after changing settings on my router to WPA2-PSK/WPA3-SAE Mixed Mode. With WPA2-PSK it work again.

[Jeran]

Thank you for letting us know! If you have the time, would you also be willing to submit feedback via the Google Home app with logs enabled to give some more information to the engineering team about this? It would be greatly appreciated!

Best regards,

Jeran

[olekstomek]

@Jeran I have just sent logs from my device. I reproduced the problem with connecting to WPA2/WPA3 mixed several times so everything should be visible. In the message I included a link to this thread because there is a lot of information here. I sent the log from the same e-mail that is assigned to my account on this forum. I hope the logs I sent will explain a lot.

[Jeran]

Awesome, thank you for sending that over! Now, just to be transparent, it may take some time for the engineering department to research this issue and look for a resolution, but every bit of feedback and logs on the subject helps a ton.

Thank you again for doing that! If you had any other questions or concerns, please let me know.

Best regards,

Jeran

[olekstomek]

Perfect. Hope you can find and fix the problem.

[Jeran]

Hey there olekstomek,

In the meantime, did you have any other questions or concerns that we can address?

Just checking up,

Jeran

[olekstomek]

Hi Jeran, currently I have no questions. Unless one thing, do you know when the problem analysis is predictable and the solution if the problem is confirmed?

[Jeran]

Hey there olextomech,

At this point in time, I do not have any information from the engineering team, sadly. I know they prioritize feature requests and bugs fixes based on the severity of the issue, as well as the amount of feedback they receive about the subject. It may be some time before they have a chance to look into this.

I'm sorry I don't have much information on this, I would share more info if I had more to share.

Best regards,

Jeran

[olekstomek]

OK, thanks. It is important that it is in the backlog. 👍

[TrendMend]

Adding to this as I am also a user of OpenWRT and finally found out today this is why my Chromecast hasn't been working for a couple months. Good to know and hopefully this is resolved.