Kafka output with SASL_SSL authentication -- message to topic failed

Connection established

2021-02-23T04:37:47.565Z INFO [publisher_pipeline_output] pipeline/output.go:143 Connecting to kafka(xxxxxxxxxxxxxxxxxxxxxxxxx:9093,yyyyyyyyyyyyyyyyyyyyyyyyy:9093,zzzzzzzzzzzzzzzzzzzz:9093)
2021-02-23T04:37:47.565Z DEBUG [kafka] kafka/client.go:100 connect: [xxxxxxxxxxxxxxxxxxxxxxxxx:9093 yyyyyyyyyyyyyyyyyyyyyyyyy:9093 zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz:9093]
2021-02-23T04:37:47.565Z INFO [publisher_pipeline_output] pipeline/output.go:151 Connection to kafka(xxxxxxxxxxxxxxxxxxxxxxxxx:9093,yyyyyyyyyyyyyyyyyyyyyyyyy:9093,zzzzzzzzzzzzzzzzzzzz:9093) established

2021-02-23T04:43:53.290Z DEBUG [kafka] kafka/client.go:385 Kafka publish failed with: kafka: client has run out of available brokers to talk to (Is your cluster reachable?)

Here is my congfiguration

output.kafka:

initial brokers for reading cluster metadata

hosts: ["xxxxxxxxxxxxxxx:9093", "yyyyyyyyyyyyyyyyyyyy:9093", "zzzzzzzzzzzzz:9093"]

message topic selection + partitioning

topic: 'test-file-data'
partition.round_robin:
reachable_only: false
required_acks: 1
compression: snappy
max_message_bytes: 1000000
sasl.mechanism: ''
version: '2.0.0'
kerberos.enabled: true
kerberos.auth_type: keytab
kerberos.keytab: /var/keytab/private/xxxx.keytab
kerberos.config_path: /etc/krb5.conf
kerberos.realm: AD.XXXXXX.COM
kerberos.username: xxxxxx
kerberos.service_name: kafka