Jigasi does not resolv DNS of SIP Server

[SchaeVHS]

Dear Devs,
many thanks for jitsi!

In my local docker-compose deployment I can't connect to my freeswitch (voip provider),
because Jigasi does not resolve the DNS entry.
I'm pretty sure it is a Jigasi bug and not docker-related:

[email protected]
JIGASI_SIP_SERVER=174.5.43.3
--> works, no problems

JIGASI_SIP_URI=username@docker-alias
JIGASI_SIP_SERVER=docker-alias
--> does not work.

Error log:
Jigasi 2022-02-28 19:10:20.130 SEVERE: [35] impl.protocol.sip.ProtocolProviderServiceSipImpl.register().444 No address found for ProtocolProviderServiceSipImpl(SIP:username@docker-alias)

I also tested inside the docker container:
I can ping docker-alias, I get correct result with dig. And also port docker-alias:5060is reachable inside the jigasi container, so the only thing left is that jigasi does not use the system resolv config?

[SchaeVHS]

I found the issue:
Jigasi is searching a SRV record, which is usually not provided by local deployments or docker.

If you set the jigasy proxy system, it falls back to normal DNS queries and works.
For docker this is reachable by setting the following in the .env file:

JIGASI_SIP_PORT=5060
JIGASI_SIP_TRANSPORT=UDP