V20 U8: Bulk deploying SessionTimerBehaviour change across Generic SIP Trunks without losing DID mappings?

Flipper

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Hello,

We manage a large fleet of instances running Version 20.0 Update 8 (Build 1131 Release), split between on-premise and Hosted environments.

On several of our systems using the Generic SIP Trunk template, we are encountering an upstream carrier variance regarding RFC 4028. The carrier negotiates the session timer initially, but fails to respond to the periodic session refresh updates sent by the PBX, causing calls to cleanly disconnect exactly at the 30-minute mark (1800-second expiration).

To resolve this across our fleet, we need to bypass the session timer enforcement on the 3CX side. Reviewing the stock factory templates, advanced session timing properties are not explicitly declared by default.

Question 1: Can someone confirm if injecting <field name="SessionTimerBehaviour">0</field> into the <device> section of a custom generic template copy is the correct schema parameter to instruct the 3CX core engine to completely disable/ignore the session timer mechanism for that specific trunk?

Question 2: Because we manage dozens of downstream customers with thousands of active DIDs already mapped to internal endpoints (Ring Groups, Digital Receptionists, and Users), we cannot afford to recreate the trunks from scratch, as this unassigns the DIDs.

For our Hosted instances where we do not have direct OS file system access, if we import the modified XML via Admin -> Advanced -> Templates -> Provider Templates and hit Save, will the built-in V20 template synchronization tool cleanly push this parameter update to the active trunks without dropping or breaking our existing DID routing configurations?

Thank you for any operational insights!
 
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Hello,

There is no way to adjust the use of session-timer from the 3CX side. The functionality is buried deep in the call manager and cannot be disabled via template. If the provider supports timers then we use it, if not then we do not.
If your carrier supports the use of session-timers but does not reply to them then this is something you need to look at with your carrier. They need to disable the support for timers from their end, not 3CX.
 
Thanks, I was really hoping it could be disabled. Will be shopping for a new provider
 
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