Unity Connection Cluster - Delay answering after failover

[dave.yeskey]

Unity Connection 7.1.5 servers in HA with SIP trunk integration to CUCM
6.1.3.  I am testing the failover and after unplugging the subscriber server
there is an initial delay before the publisher began accepting calls (which is
normal).

But once it is failed over it takes approximately 4 seconds after pressing 
the messages key before the publisher server answers.  From speaking with
another engineer, I don't believe this is normal.

I have a TAC case open and they say it could be SIP timeouts.  Has anyone else
seen this?  Is it normal?  I may need to switch to SCCP if the customer finds
this unacceptable.

Thanks.

[Jonathan Schulenberg · Accepted solution]

It very well may be a SIP timeout although I'm confused why you are posting to the forum if you already have a TAC engineer helping you?

There are few service parameters in UCM that impact this. You can adjust them but will likely still see a second or two delay in this scenario: https://supportforums.cisco.com/message/3115266#3115266

[dave.yeskey]

Thanks for the link.  And I don't think the support forums and TAC are mutually exclusive.

[dave.yeskey]

On the SIP Profile for the Connections trunk lower Retry INVITE parameter.  The Integration Guide

says to enter a value of 5 or less but doesn't give an explanation why.  I set it at 2 and now there is

no delay.

[Rob Huffman]

Hi Dave,

Thanks for posting back with your results here (+5 points for this

great follow-up!)

Cheers!

Rob