Plantronics + Polycom. Now together as Poly Logo

IP550 4.0.9 TCPPreferred failover conditions

Occasional Visitor

IP550 4.0.9 TCPPreferred failover conditions

Hello all,


I have a quick question which I don't believe has a thread already.  I have a IP550 running 4.0.9 set to use 'TCPPreferred' as the transport method and I am seeing on my PBX after several days post-restart (and after flushing registrations on the PBX), the phone registers over TCP and after an unknown period of time concurrently registers over UDP.  In the end, there are two registrations with the same call id and an inbound call is delivered twice to the same user.  I was previously running 4.0.4 and the issue didnt occur.  What are the failover conditions when the phone decides to switch to UDP?  There is a mention of it here, but there was never a response.  I was just curious if it has been reported before.


Message 1 of 2
Polycom Employee & Community Manager

Re: IP550 4.0.9 TCPPreferred failover conditions

Hello Rob,

welcome to the Polycom Community.

The original poster never replied and neither followed up earlier posts and/or opened a support ticket as recommended.


Without this Polycom support is not able to gather the relevant required information and troubleshoot or provide a software fix for this.


Could you kindly work with your Polycom reseller and/or raise a PayPerIncident Ticket if outside warranty so we can check this ?

Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.

Best Regards

Steffen Baier

Polycom Global Services

The title Polycom Employee & Community Manager is a community setting and does not reflect my role. I am just a simple volunteer in the community like everybody else. All posts and words are my own & do not represent the views of Employer.


Notice: This community forum is not an official Poly support resource, thus responses from Poly employees, partners, and customers alike are best-effort in attempts to share learned knowledge. If you need immediate and/or official assistance please open a service ticket through your proper support channels.
Please also ensure you always check the VoIP , Video Endpoint , Skype for Business , PSTN or RPM FAQ's
Message 2 of 2