Phones wont provision after upgrade to V20

[fair-rite]

We upgraded our locally hosted V18 to V20.

After the upgrade we noticed that the phone books were not working and extension names were not displaying when users called.

Traced this back to old settings in the provisioning files. All our links setup in the past were http:\\path

With V20 it changed to https. Figured it was an easy enough fix to change them all to HTTPS but no go. Found out we need a cert and likely why the old admin was using http. Bought and applied the cert but still no go.

The web admin interface shows the cert as valid. If i try to import the root cert to the phone or the server cert the phone says they already exist.

Were running T46G's and are in the process of upgrading but it will be awhile before we can deploy hundreds of them. In the mean time i need to get the T46G's working again.

Any idea on why the phones wont provision? I've tried with "only accept trusted certificates" disabled and enabled. Same issue.

The phones attempt to provision then go to "Skip update"

I have tried using the 3CX firmware 28.83.0.136 but that did not work. Our phones are mostly running 28.83.0.160 from Yealink.

Edit: The phone will not auto provision. But if i manually provision the phone with the server link, name and pass. The phone will provision properly and everything works.

 

[JohnS_3CX]

Hi @fair-rite

Your case is a bit complex now, you upgraded late in the lifetime of V20, you have an on-premises installation, custom FQDN, custom certificates, and EOL phones.

On our 2023 blog post we prepared customers about the V20 Split DNS requirement: https://www.3cx.com/blog/releases/split-dns-on-prem/ which I will guess you were not aware of.

As for your custom certs and chain, this is up to you to check for completion along with intermediate certificates, and also to ensure that the Yealinks support your Root CA. If not, you will have to upload the CA to the phones or change certs to ones that Yealink Supports.

The fact that they are EOL phones may complicate this as their CA list will not be kept up to date. They also do not support RPS via 3CX anymore (something that we also use for local phones now so you have to go disable RPS on Phones > Options). You might need to look up Yealink's documentation on how to handle this or you could contact a 3CX Partner to help if you don't have the time to look into this. I wish you had done the migration sooner so you would have the time to address these points ahead of schedule, but these are your most immediate options:

1. edit each and every T46G phone under all extensions, and change the network interface to use the IP (it will give plain http which is not secure but will work like in V18). This is a band aid solution and not expected to work forever in future releases - you need to set up Split DNS to remain supported.

2. You can also set up DHCP option 66 to point to your server, and reset the Yealinks one by one so they will automatically go fetch their config. This option must be disabled under phones > options so that the config URL can remain static.