I have a kafka installation running within in kubernetes cluster. I have a pod running a spring boot application which is using the default bootstrap.servers (localhost:9092) configuration and not the one passed in (bootstrap.kafka.svc.cluster.local:9092). The pod then fails to start as kafka is not running on localhost.
Here is my spring boot configuration
spring:
kafka:
consumer:
group-id: spring-template
auto-offset-reset: earliest
bootstrap-servers: "bootstrap.kafka.svc.cluster.local:9092"
producer:
bootstrap-servers: "bootstrap.kafka.svc.cluster.local:9092"
bootstrap-servers: "bootstrap.kafka.svc.cluster.local:9092"
When setting up the consumers on startup the group id and auto-offset-reset are being correctly passed in from the above configuration. However the bootstrap-servers configuration is not and the application is actually using localhost:9092 as per the log below
2019-03-11 07:34:36.826 INFO 1 --- [ restartedMain] o.a.k.clients.consumer.ConsumerConfig : ConsumerConfig values:
auto.commit.interval.ms = 5000
auto.offset.reset = earliest
bootstrap.servers = [localhost:9092]
check.crcs = true
client.id =
connections.max.idle.ms = 540000
default.api.timeout.ms = 60000
enable.auto.commit = true
exclude.internal.topics = true
fetch.max.bytes = 52428800
fetch.max.wait.ms = 500
fetch.min.bytes = 1
group.id = spring-template
heartbeat.interval.ms = 3000
interceptor.classes = []
internal.leave.group.on.close = true
isolation.level = read_uncommitted
key.deserializer = class org.apache.kafka.common.serialization.StringDeserializer
max.partition.fetch.bytes = 1048576
max.poll.interval.ms = 300000
max.poll.records = 500
metadata.max.age.ms = 300000
metric.reporters = []
metrics.num.samples = 2
metrics.recording.level = INFO
metrics.sample.window.ms = 30000
partition.assignment.strategy = [class org.apache.kafka.clients.consumer.RangeAssignor]
receive.buffer.bytes = 65536
reconnect.backoff.max.ms = 1000
reconnect.backoff.ms = 50
request.timeout.ms = 30000
retry.backoff.ms = 100
sasl.client.callback.handler.class = null
sasl.jaas.config = null
sasl.kerberos.kinit.cmd = /usr/bin/kinit
sasl.kerberos.min.time.before.relogin = 60000
sasl.kerberos.service.name = null
sasl.kerberos.ticket.renew.jitter = 0.05
sasl.kerberos.ticket.renew.window.factor = 0.8
sasl.login.callback.handler.class = null
sasl.login.class = null
sasl.login.refresh.buffer.seconds = 300
sasl.login.refresh.min.period.seconds = 60
sasl.login.refresh.window.factor = 0.8
sasl.login.refresh.window.jitter = 0.05
sasl.mechanism = GSSAPI
security.protocol = PLAINTEXT
send.buffer.bytes = 131072
session.timeout.ms = 10000
ssl.cipher.suites = null
ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1]
ssl.endpoint.identification.algorithm = https
ssl.key.password = null
ssl.keymanager.algorithm = SunX509
ssl.keystore.location = null
ssl.keystore.password = null
ssl.keystore.type = JKS
ssl.protocol = TLS
ssl.provider = null
ssl.secure.random.implementation = null
ssl.trustmanager.algorithm = PKIX
ssl.truststore.location = null
ssl.truststore.password = null
ssl.truststore.type = JKS
value.deserializer = class org.apache.kafka.common.serialization.StringDeserializer
2019-03-11 07:34:36.942 INFO 1 --- [ restartedMain] o.a.kafka.common.utils.AppInfoParser : Kafka version : 2.0.1
2019-03-11 07:34:36.945 INFO 1 --- [ restartedMain] o.a.kafka.common.utils.AppInfoParser : Kafka commitId : fa14705e51bd2ce5
2019-03-11 07:34:37.149 WARN 1 --- [ restartedMain] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=spring-template] Connection to node -1 could not be established. Broker may not be available.
I have kubernetes service called bootstrap, running in namespace kafka in the kubernetes cluster. Here is a snippet of the log file. Why is the spring boot application not picking up the configured bootstrap.servers configuration
