I did and now it hangs on the first send.  Here's my output: (hopefully won't destroy formatting).The "::: Writing 1 :::" should output a line like that for each of 6 writes, but only the first is called, then hangs until timeout.
[pool-10-thread-1-ScalaTest-running-KafkaSpec] INFO org.apache.kafka.clients.producer.ProducerConfig - ProducerConfig values: compression.type = none metric.reporters = [] metadata.max.age.ms = 300000 metadata.fetch.timeout.ms = 60000 reconnect.backoff.ms = 50 sasl.kerberos.ticket.renew.window.factor = 0.8 bootstrap.servers = [192.168.99.100:9092] retry.backoff.ms = 100 sasl.kerberos.kinit.cmd = /usr/bin/kinit buffer.memory = 33554432 timeout.ms = 30000 key.serializer = class org.apache.kafka.common.serialization.ByteArraySerializer sasl.kerberos.service.name = null sasl.kerberos.ticket.renew.jitter = 0.05 ssl.keystore.type = JKS ssl.trustmanager.algorithm = PKIX block.on.buffer.full = false ssl.key.password = null max.block.ms = 60000 interceptor.classes = null sasl.kerberos.min.time.before.relogin = 60000 connections.max.idle.ms = 540000 ssl.truststore.password = null max.in.flight.requests.per.connection = 5 metrics.num.samples = 2 client.id = producer-1 ssl.endpoint.identification.algorithm = null ssl.protocol = TLS request.timeout.ms = 30000 ssl.provider = null ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1] acks = 1 batch.size = 16384 ssl.keystore.location = null receive.buffer.bytes = 32768 ssl.cipher.suites = null ssl.truststore.type = JKS security.protocol = PLAINTEXT retries = 0 max.request.size = 1048576 value.serializer = class org.apache.kafka.common.serialization.StringSerializer ssl.truststore.location = null ssl.keystore.password = null ssl.keymanager.algorithm = SunX509 metrics.sample.window.ms = 30000 partitioner.class = class org.apache.kafka.clients.producer.internals.DefaultPartitioner send.buffer.bytes = 131072 linger.ms = 0
[pool-10-thread-1-ScalaTest-running-KafkaSpec] INFO org.apache.kafka.common.utils.AppInfoParser - Kafka version : 0.10.1.0-SNAPSHOT[pool-10-thread-1-ScalaTest-running-KafkaSpec] INFO org.apache.kafka.common.utils.AppInfoParser - Kafka commitId : 319c6e7195143c1f  ::: Writing 1 ::::[kafka-producer-network-thread | producer-1] WARN org.apache.kafka.clients.NetworkClient - Error while fetching metadata with correlation id 0 : {lowercaseStrings=LEADER_NOT_AVAILABLE}org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 59860 ms.
      From: Ismael Juma <[EMAIL PROTECTED]>
 To: [EMAIL PROTECTED]; Greg Zoller <[EMAIL PROTECTED]>
 Sent: Wednesday, April 13, 2016 5:54 PM
 Subject: Re: [0.10.1.0-SNAPSHOT] KafkaProducer.close() not committing
   
Hi Greg,

It may be worth passing a callback to the `send` to see if there's any
error (or calling `get` on the Future returned).

Ismael

On Wed, Apr 13, 2016 at 2:59 PM, Greg Zoller <[EMAIL PROTECTED]lid>
wrote:
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