[OpenSIPS-Users] OpenSIPS and Teams

[David Rickard]

Hello all,

I'm currently trying to set up OpenSIPS as an SBC for Teams. Basically I've got a need to run a load of phones (around 400) on a FreePBX which will be attached to Teams for internal calls. So the intention is to run a SIP trunk from FreePBX to OpenSIPS, then have OpenSIPS sitting in the DMZ (on a public IP externally, and internal IP for the PBX) talking out to Teams. Set routes up both sides for the extensions, and that's it.

However, easier said than done. I'm not a SIP expert, and I'm feeling my way with this, but to no avail really. I'd go and buy an SBC, but budgets are limited and I'd like to make this work.

I've followed the OpenSIPS Blog article about it (https://blog.opensips.org/2019/09/16/opensips-as-ms-teams-sbc/), but that didn't get me far - it's a pretty old article and I'm not sure how relevant it still is. I then moved onto an example config I found (https://github.com/w01w13/opensips-teams-sbc/blob/master/etc/opensips/config/opensips.cfg.m4), but it does warn it's experimental and again, I've not had much luck. Thus far I've managed to get TLS up (verified with dr_gw_status) but it doesn't appear to be sending the OPTIONS back properly. I can't figure out how to get it to dump full traces so I can see what is happening and debug it.

I'm using LE certs right now, with a plan to move to something else soon.

Does there exist any example configs, or recent guides on what to do to attach to Teams? I've seen many people mention they're doing it, so I know it's possible, I've just been unable to find a working example to customise.

I do have a config, I can post it, but it's nothing particularly coherent or useful at this point, I don't think. I've been chopping and changing so much I'm not sure where I am.

I've got RHEL 9 with OpenSIPS 3.6 from the official repository.

Thanks in advance, if anybody can help me.

David Rickard