Communication Manager - SIP call failed 422 Session Interval Too Small
SOLN278648 | Version: 9.0 | Published: 11/13/2015 | Updated: 07/23/2020
Available To: Customer
Categories: Avaya Aura® Communication Manager, Configuration, Interoperability, Troubleshooting
Details
  • Avaya Communication Manager
  • SIP Provider  <--> SBC <---> SM <---> CM

 

Problem Clarification

I) POM nail up calls are failed. the calls are not connecting to agent.

SBC with Min-SE ---> 600/1200

CM SIP trunk Min-SE (display trunk-group X / Preferred Minimum Session Refresh Interval(sec) ----->  900/1800

Call starts at SBC with a Min-SE of 1200. It reaches sends the call out its designated SIP trunk towards the Session Manager. Session Manager sees that based on the dial pattern, this call is going to CM. It forward’s the INVITE to CM without changing it. It reaches the CM and it responds to the invite.The Min-SE configured in the CM Trunk Group is 900. It would present a 422 stating "I want to use 1800 instead".
 
CM will send the 422 Session Interval Too Short event to SIP SBC via SM and CM will expect the re-invite message from SIP SBC (via SM) to re-negotiate it.
 
The POM need to have proposed a Min-SE that is equal or greater than the Min-SE sent by our CM "422 Session Interval Too Small" message through a re-INVITE message for the negotiation.
 
In our scenario CM sends the 422 Session Interval Too Short event to POM  but CM didn't received the re-invite from POM for the negotiation.
 
ii) Call are working fine, but in traces we see lot of "422 Session Interval Too Small " events.

 

Solution