The mt-broker-ingress needs to authenticate requests to its underlying channel as described in https://gist.github.com/creydr/8b694956f27b0cb338b3576f3a893879#broker-ingress-to-channel.
The mt-broker-ingress needs to authenticate requests to its underlying channel as described in https://gist.github.com/creydr/8b694956f27b0cb338b3576f3a893879#broker-ingress-to-channel.