Solved Upgraded v14 to v15.5, SIP using TCP now?

[Xestrix]

Hello all,

I'm experiencing a strange issue with and upgrade I just performed. Moving from an up-to-date v14 to v15.5, I noticed that post-upgrade, outbound calls were failing (inbound were fine).

Checking Wireshark, there were no differences in the SIP Invite requests except that in v14 the request was sent using UDP, and in v15.5 the request sent using TCP. I've checked another v15.5 install, and the issue is not present there.

I restored a backup and performed the update a second time with the same result as well.

Any ideas why this particular upgrade changed the outbound behaviour, and any ideas on how I can restore the previous behaviour?

Thanks!

 

[cobaltit]

3CX will tell you that it is a problem with your provider. Haven't run into the situation myself to confirm. Basically in v15.5 they now lookup SRV records for providers which can dictate how they connect. See this post:

https://www.3cx.com/community/threads/version-15-5-issue-with-nexvortex.49293/

There's another thread somewhere where they gave the syntax on how to force the protocol which I can't find at the moment and it's not documented in the manual. I'll look for that now.

 

[cobaltit]

Ok found it. Try "transport-udp" in front of the registrar/server/gateway hostname.

https://www.3cx.com/community/threa...the-machine-but-3cx-cant-resolve-fqdns.55968/

 

[Xestrix]

Ok found it. Try "transport-udp" in front of the registrar/server/gateway hostname.

https://www.3cx.com/community/threa...the-machine-but-3cx-cant-resolve-fqdns.55968/

That sounds promising, I'll give that a shot this evening, thanks!

That whole thread was very informative.

 

[cobaltit]

And now that I read it all the way through it looks like you would put your SIP server in both the SIP server field and outbound proxy field to force UDP.

Good luck!

 

[Xestrix]

put your SIP server in both the SIP server field and outbound proxy field to force UDP

This resolved my issue immediately; thanks for the on-point assistance!

 

[YiannisH_3CX]

Glad to see the issue has been resolved.