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David Przywara's avatar
David Przywara
Copper Contributor
Apr 26, 2023

Yealink MP56 with Teams SBA Issue

Has anyone gotten Yealink MP56, or any other Teams IP phone working with SBA? We've been testing failover to SBA by restricting access to the internet for Teams devices. The Windows desktop client fa...
Calling
SBA
teams
beyonduc's avatar
beyonduc
Copper Contributor
Jun 30, 2023
Hi,

Did you have any chance to resolve this issue? I have similar scnario but with Yealink MP54 phones.
Any suggestions?

Regards
  • David Przywara's avatar
    David Przywara
    Copper Contributor
    Jun 30, 2023
    We resolved the issue yesterday with Microsoft escalations support. There is a bug with IP phone firmware where they do not support wildcard certificates used on the SBA appliance. Generating a CSR on the SBA and getting that signed resolved the issue.
    • Shalid_Chalil's avatar
      Shalid_Chalil
      Copper Contributor
      Jul 03, 2023

      Thanks David Przywara 

       

      We are not using a wildcard, I have shared certificates for the SBC and SBA.  I reproduced the issue by blocking the internet access to the phone. But no luck, it never shows the banner for disconnection. Also, it doesn't allow users to make or receive any calls. strangely I cannot even see the phone connectivity details in the SBA. All the team's clients except the phones are in the connected team clients. 

       

      The phone firmware is updated and it is in the latest.  to be safe, I have uploaded the root CA certificates to the phone. 

       

      Any suggestions ..

       

      Regards

      • David Przywara's avatar
        David Przywara
        Copper Contributor
        Jul 03, 2023
        Are you using internal CA or 3rd party certificates? For your testing, if phones are on a different VLAN make sure they have access to internal DNS and the SBA appliance. Also make sure the FQDN used in the SBA policy has the same name and casing as the certificates installed on the SBA.

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