Can I bind DNS using Loadbalancer? In a private cloud environment

[peter-hst]

we using strimzi-v0.32.0 , After trying various configurations, it seems that it cannot bind DNS, right? It is possible to produce/consume messages using LB-IP directly. Could you help support ? Thanks a lot!

    listeners:
      - name: plain
        type: internal
        port: 9092
        tls: false
      - name: external
        port: 9094
        # https://strimzi.io/docs/operators/0.32.0/configuring#property-listener-config-annotations-reference
        type: loadbalancer
        tls: true
        authentication:
          type: scram-sha-512
        configuration:
          # useServiceDnsDomain: true
          bootstrap:
            # host: kafka-bootstrap-demo.test.com
            loadBalancerIP: 10.237.203.34
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-bootstrap-demo.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"
          brokers:
          - broker: 0
            # host: kafka-broker-demo-0.test.com
            loadBalancerIP: 10.237.201.45
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-broker-demo-0.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"
          - broker: 1
            # host: kafka-broker-demo-1.test.com
            loadBalancerIP: 10.237.203.118
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-broker-demo-1.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"
          - broker: 2
            # host: kafka-broker-demo-2.test.com
            loadBalancerIP: 10.237.202.160
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-broker-demo-2.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"

when I enabled/disabled that host: kafka-bootstrap-demo.test.com, host: kafka-broker-demo-0.test.com, host: kafka-broker-demo-1.test.com, host: kafka-broker-demo-2.test.com options(only for nodeport?), it doesn't work. I don't knows the reason.

[peter-hst]

If I use the following options, does it support Loadbalancer?

listeners:
  #...
  - name: external
    port: 9094
    type: loadbalancer
    tls: true
    authentication:
      type: tls
    configuration:
      brokers:
      - broker: 0
        advertisedHost: kafka-broker-demo-0.test.com
        advertisedPort: 9094
      - broker: 1
        advertisedHost: kafka-broker-demo-1.test.com
        advertisedPort: 9094
      - broker: 2
        advertisedHost: kafka-broker-demo-2.test.com
        advertisedPort: 9094

[scholzj]

Strimzi integrates with Kubernetes and not with your DNS. If you want to use custom DNS names, you have to set them up yourself or using other tools. The documentation (and multiple previous discussions) covers how to add additional names to the certificates (alternativeNames property) or how to override advertised hostnames (advertisedHost property). Please check there for examples.

[peter-hst]

Hello Scholzj @scholzj Thank you ! do you have the link?

this one?

[scholzj]

I do not have a link at hand. You can search for the fields I mentioned.

[peter-hst]

It works! Thanks a lot!

            alternativeNames:
              - kafka-bootstrap-demo.test.com ### It works! only added this line
              - kafka-broker-demo-0.test.com ### borkers list, is it right?
              - kafka-broker-demo-1.test.com ### borkers list, is it right?
              - kafka-broker-demo-2.test.com ### borkers list, is it right?

you solved a big deal. 😀

can I settings blow options?

    listeners:
      - name: plain
        type: internal
        port: 9092
        tls: false
      - name: external
        port: 9094
        # https://strimzi.io/docs/operators/0.32.0/configuring#property-listener-config-annotations-reference
        type: loadbalancer
        tls: true
        authentication:
          type: scram-sha-512
        configuration:
          # useServiceDnsDomain: true
          bootstrap:
            # host: kafka-bootstrap-demo.test.com
            alternativeNames:
              - kafka-bootstrap-demo.test.com
            loadBalancerIP: 10.237.203.34
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-bootstrap-demo.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"
          brokers:
          - broker: 0
            # host: kafka-broker-demo-0.test.com
            advertisedHost: kafka-broker-demo-0.test.com
            advertisedPort: 9094
            loadBalancerIP: 10.237.201.45
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-broker-demo-0.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"
          - broker: 1
            # host: kafka-broker-demo-1.test.com
            advertisedHost: kafka-broker-demo-1.test.com
            advertisedPort: 9094
            loadBalancerIP: 10.237.203.118
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-broker-demo-1.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"
          - broker: 2
            # host: kafka-broker-demo-2.test.com
            advertisedHost: kafka-broker-demo-2.test.com
            advertisedPort: 9094
            loadBalancerIP: 10.237.202.160
            annotations:
              external-dns.alpha.kubernetes.io/hostname: kafka-broker-demo-2.test.com.
              external-dns.alpha.kubernetes.io/ttl: "60"

[scholzj]

That should be valid, yes. You don't need to override the advertisedPort, but it is not an issue, it will basically just not change anything as it already was 9094.

[peter-hst]

I'll drop the advertisedPort: 9094 line. cool! Thanks!