Thanks, Henning, Lyubomir

I'm using P-CSCF, I-CSCF, S-CSCF (with MySQL and DRA integration), without any media handling (it's all bypass) and probably with little/no NAT-handling functions. The charging/billing is separate (we've different services for that); it's mainly to get the SIP flows working reliably, both with and without ipsec. I have most of it working, but I'm not sure about how far it will scale (especially with ipsec) and I still have problems to iron out (at least one memory leak), which maybe others have already resolved already somehow.

One problem that I've already fixed (I think) is the prometheus metric for kamailio_ims_usrloc_pcscf_registered_impus. I see in the source code that the function get_number_of_impu() counts the wrong thing. I'm going to try to make a Pull Request for this (a first for me) when I get a chance. - https://github.com/kamailio/kamailio/blob/6.0.5/src/modules/ims_usrloc_pcscf...

The point is that I'd be interested if anyone has this working reliably at scale, to know what problems were encountered/resolved, what pitfalls to avoid, etc. In the meantime, I'll check your repository, Lyubomir, and see what I find.

James

On Wed, 7 Jan 2026 at 14:50, Lyubomir Yatanski l.yatanski@gmail.com wrote:

Hi James,

I'm playing around with IMS: https://github.com/lyatanski/ims

Some of the aspects of this effort will be scaling and high availability in Kubernetes. Currently I have prepared only rudimentary Helm charts (and they mostly do not work yet)

As my time is limited and my scope is quite broad - including testing tool, monitoring and billing integration, I have not made tremendous advancements.

If you think we can share knowledge and experience on the subject, please let me know.

Regards, Lyubomir Yatanski

On Tue, Jan 6, 2026, 5:36 PM Henning Westerholt via sr-users sr-users@lists.kamailio.org wrote:

...

Hello James,

I think it's used in production from different companies. But there are many IMS modules, and there are probably used differently depending on the scenario. They are also variations in the production readiness and/or features of the IMS modules.

Some of our customers are using the charging/pre-paid and diameter parts in production, to give a specific example.

In which area you are interested?

Cheers,

Henning

-- Kamailio services - https://gilawa.com

...

-----Original Message----- From: James Browne via sr-users sr-users@lists.kamailio.org Sent: Dienstag, 6. Januar 2026 14:16 To: Kamailio (SER) - Users Mailing List sr-users@lists.kamailio.org Cc: James Browne james@frideo.com Subject: [SR-Users] Production IMS with kamailio 6

Hi Has any of us ever successfully (or know someone who has) set up an IMS with kamailio in production that scales to thousands of users? I'm working on an POC and I might be able to use some help.

James __________________________________________________________ Kamailio - Users Mailing List - Non Commercial Discussions -- sr- users@lists.kamailio.org To unsubscribe send an email to sr-users-leave@lists.kamailio.org Important: keep the mailing list in the recipients, do not reply only to the sender!

---

Kamailio - Users Mailing List - Non Commercial Discussions -- sr-users@lists.kamailio.org To unsubscribe send an email to sr-users-leave@lists.kamailio.org Important: keep the mailing list in the recipients, do not reply only to the sender!