Hi, I'm in the progress of testing MTS working with fedora-messaging. I'm confused on these two things:

What is the username to connect to fedora-messaging broker? Is message-tagging-service the default username used for the connection? If no, could you please allow MTS instance to connect to broker with username message-tagging-service?

The username is the tls certificate name, so since your cert is 'mts' that should be the username as well.
If you really need us to change it, we would need to issue you new certs.

What is the value of ca_cert? Do I need to request a ca_cert specifically?

No, thats the certificate authority cert... you can find it in the fedora-messaging rpm package as "/etc/fedora-messaging/cacert.pem" and the staging one as "/etc/fedora-messaging/stg-cacert.pem"

See https://fedora-messaging.readthedocs.io/en/stable/configuration.html for more info... or feel free to ask here if you have further questions or need anything more.

Hope that helps.

:eyeglasses:

Thanks.