WiFi Calling not working

In retrospect it probably wasn’t that useful to get carrier info (since this is wifi :facepalm: ). Can you provide ISP info as well?

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makes sense :sweat_smile:
I’m with TalkTalk UK

@ryan This is what GoogleDNS returns when you look up a WiFi calling server:

DNS server handling your query:
DNS server’s address:

Non-authoritative answer:
origin = a4.nstld.com
mail addr = mdnshelp.verisign.com
serial = 1394626786
refresh = 28800
retry = 7200
expire = 1209600
minimum = 86400
mnc030.mcc234.pub.3gppnetwork.org nameserver = j4.nstld.com.
mnc030.mcc234.pub.3gppnetwork.org nameserver = k4.nstld.com.
mnc030.mcc234.pub.3gppnetwork.org nameserver = l4.nstld.com.
mnc030.mcc234.pub.3gppnetwork.org nameserver = g4.nstld.com.
mnc030.mcc234.pub.3gppnetwork.org nameserver = f4.nstld.com.
mnc030.mcc234.pub.3gppnetwork.org nameserver = a4.nstld.com.

This is what Cloudflare returns
DNS server handling your query:
DNS server’s address:

** server can’t find mnc030.mcc234.pub.3gppnetwork.org.frog.qrq.de: NOTIMP


Same problem here…
Three in the UK.
iPhone 6s with 11.3 and configured in iPhone DNS settings.

I’m just looking into this, thanks for your patience. It seems that the NSs at wip.mnc020.mcc234.pub.3gppnetwork.org are broken for QNAME minimisation, as they don’t respond to anything besides the full name. I’ll add overrides for this NS set in the next upgrade.


Awesome stuff thanks @mvavrusa and @ryan

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Let me know if I can provide additional details, but confirming that the use of and prevents Wi-Fi Calling (Verizon Wireless) from working on my Android 8.1 device.

Confirmed this issue at home (Verizon FiOS) and work (Comcast Business).

Wi-Fi Calling shows as connected in the notification bar and an incoming call will ring… but I cannot hear anyone and they cannot hear me. Outgoing calls attempt to connect for about 30 seconds before timing out.

@mvavrusa I am also having issues in Australia.
ISP is Telstra Broadband. Mobile provider is also Telstra. Wifi calling works fine when I use Telstra dns or OpenDNS. Does not work when I use Cloudflare…
iPhone X on 11.3

Telstra DNS Servers are here: https://crowdsupport.telstra.com.au/t5/Broadband-nbn/How-To-Check-Your-DNS-Settings/ta-p/181966
Telstra specific info on Wifi Calling is listed here:

Could you check whether you’re still seeing issues? Most of the names in pub.3gppnetwork.org zone should be resolving now.

Can confirm working now on Three UK

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I can confirm the records are now resolving correctly.

No dice on Verizon in the US.

mvavrusa - if you look at the bottom of this thread (maybe just above this reply), drsuse still cannot do WiFi Calling on Verizon, which will be a concern for me as well.

In a different thread (https://community.cloudflare.com/t/higher-latency-ping-from-new-york-city/15431/23), we solved one Verizon problem, but this one seems to be different. Can you get the same CF engineers involved?

Sure, I’ll take a look. The WiFi calling problem should be fixed. The issue was with the parent zone (3gppnetwork.org), in which all participating operators get assigned a CNAME, didn’t respond properly to minimal name. There may be issues with individual operators, I’ll try to find out which code is assigned to Verizon US and investigate.

Hey - mvavrusa - any news?
Yesterday morning, I went from Verizon DSL to Verizon FIOS 1Gbps. Wow !!!
Anyway, as I am using as the designated DNS in the new router (so covers all my devices) and have Simple DNSCrypt in one of my PCs, would be nice to know whether Verizon WiFi Calling has any issues.

mvavrusa - anything interesting? Thanks.

Don’t forget to include the @ before the username, otherwise @mvavrusa might not get the same alert :slight_smile:

Hi, I don’t see any problems for Verizon, it should work depending on which of their networks you’re assigned to. There’s one MNC that’s not resolvable currently: http://dnsviz.net/d/epdg.epc.mnc480.mcc311.pub.3gppnetwork.org/dnssec/ I’ll try to reach out.

Hi, wifi calling is still not working on my iPhone. 11.3 here w/ T-Mobile USA. @mvavrusa could you help?

There’s one MNC/MCC subdomain for T-Mobile that’s broken. Can you tell me which PoP are you hitting to help me investigate? dig +short CHAOS TXT id.server @