I am having a hard time connection to a machine running Kafka from a client running a Faust script.The script looks like this:
import faust
import logging
from asyncio import sleep
class Test(faust.Record):
msg: str
app = faust.App('myapp', broker='kafka://10.0.0.20:9092')
topic = app.topic('test', value_type=Test)
@app.agent(topic)
async def hello(messages):
async for message in messages:
print(f'Received {message.msg}')
@app.timer(interval=5.0)
async def example_sender():
await hello.send(
value=Test(msg='Hello World!'),
)
if __name__ == '__main__':
app.main()
When I run the script:
# faust -A myapp worker -l info
┌ƒaµS† v0.8.1─┬─────────────────────────────────────────────────┐
│ id │ myapp │
│ transport │ [URL('kafka://10.0.0.20:9092')] │
│ store │ memory: │
│ web │ http://hubbabubba:6066 │
│ log │ -stderr- (info) │
│ pid │ 260765 │
│ hostname │ hubbabubba │
│ platform │ CPython 3.8.10 (Linux x86_64) │
│ drivers │ │
│ transport │ aiokafka=0.7.2 │
│ web │ aiohttp=3.8.1 │
│ datadir │ /Git/faust-kafka/myapp-data │
│ appdir │ /Git/faust-kafka/myapp-data/v1 │
└─────────────┴─────────────────────────────────────────────────┘
[2022-01-28 13:09:57,018] [260765] [INFO] [^Worker]: Starting...
[2022-01-28 13:09:57,021] [260765] [INFO] [^-App]: Starting...
[2022-01-28 13:09:57,021] [260765] [INFO] [^--Monitor]: Starting...
[2022-01-28 13:09:57,021] [260765] [INFO] [^--Producer]: Starting...
[2022-01-28 13:09:57,022] [260765] [INFO] [^---ProducerBuffer]: Starting...
[2022-01-28 13:09:57,024] [260765] [ERROR] Unable connect to "10.0.0.20:9092": [Errno 113] Connect call failed ('10.0.0.20', 9092)
[2022-01-28 13:09:57,025] [260765] [ERROR] [^Worker]: Error: KafkaConnectionError("Unable to bootstrap from [('10.0.0.20', 9092, <AddressFamily.AF_INET: 2>)]")
Traceback (most recent call last):
File "/Git/faust-kafka/venv/lib/python3.8/site-packages/mode/worker.py", line 276, in execute_from_commandline
self.loop.run_until_complete(self._starting_fut)
File "/usr/lib/python3.8/asyncio/base_events.py", line 616, in run_until_complete
return future.result()
File "/Git/faust-kafka/venv/lib/python3.8/site-packages/mode/services.py", line 759, in start
await self._default_start()
File "/media/eric/DISK3/Git/faust-kafka/venv/lib/python3.8/site-packages/mode/services.py", line 766, in _default_start
await self._actually_start()...
File "/Git/faust-kafka/venv/lib/python3.8/site-packages/aiokafka/client.py", line 249, in bootstrap
raise KafkaConnectionError(
kafka.errors.KafkaConnectionError: KafkaConnectionError: Unable to bootstrap from [('10.0.0.20', 9092, <AddressFamily.AF_INET: 2>)]
[2022-01-28 13:09:57,027] [260765] [INFO] [^Worker]: Stopping...
[2022-01-28 13:09:57,027] [260765] [INFO] [^-App]: Stopping...
[2022-01-28 13:09:57,027] [260765] [INFO] [^-App]: Flush producer buffer...
[2022-01-28 13:09:57,028] [260765] [INFO] [^--TableManager]: Stopping...
[2022-01-28 13:09:57,028] [260765] [INFO] [^---Fetcher]: Stopping...
[2022-01-28 13:09:57,028] [260765] [INFO] [^---Conductor]: Stopping...
[2022-01-28 13:09:57,028] [260765] [INFO] [^--AgentManager]: Stopping...
[2022-01-28 13:09:57,029] [260765] [INFO] [^Agent: myapp.hello]: Stopping...
[2022-01-28 13:09:57,029] [260765] [INFO] [^--ReplyConsumer]: Stopping...
[2022-01-28 13:09:57,029] [260765] [INFO] [^--LeaderAssignor]: Stopping...
[2022-01-28 13:09:57,029] [260765] [INFO] [^--Consumer]: Stopping...
[2022-01-28 13:09:57,030] [260765] [INFO] [^--Web]: Stopping...
[2022-01-28 13:09:57,030] [260765] [INFO] [^--CacheBackend]: Stopping...
[2022-01-28 13:09:57,030] [260765] [INFO] [^--Producer]: Stopping...
[2022-01-28 13:09:57,030] [260765] [INFO] [^---ProducerBuffer]: Stopping...
[2022-01-28 13:09:57,031] [260765] [INFO] [^--Monitor]: Stopping...
[2022-01-28 13:09:57,032] [260765] [INFO] [^Worker]: Gathering service tasks...
[2022-01-28 13:09:57,032] [260765] [INFO] [^Worker]: Gathering all futures...
[2022-01-28 13:09:58,033] [260765] [INFO] [^Worker]: Closing event loop
Kafka (v.2.8.1) is running on 10.0.0.20, port 9092. The Kafka configuration looks like this:
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# see kafka.server.KafkaConfig for additional details and defaults
############################# Server Basics #############################
# The id of the broker. This must be set to a unique integer for each broker.
broker.id=0
############################# Socket Server Settings #############################
# The address the socket server listens on. It will get the value returned from
# java.net.InetAddress.getCanonicalHostName() if not configured.
# FORMAT:
# listeners = listener_name://host_name:port
# EXAMPLE:
# listeners = PLAINTEXT://your.host.name:9092
listeners=PLAINTEXT://:9092
# Hostname and port the broker will advertise to producers and consumers. If not set,
# it uses the value for "listeners" if configured. Otherwise, it will use the value
# returned from java.net.InetAddress.getCanonicalHostName().
advertised.listeners=PLAINTEXT://localhost:9092
# Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details
#listener.security.protocol.map=PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL
# The number of threads that the server uses for receiving requests from the network and sending responses to the network
num.network.threads=3
# The number of threads that the server uses for processing requests, which may include disk I/O
num.io.threads=8
# The send buffer (SO_SNDBUF) used by the socket server
socket.send.buffer.bytes=102400
# The receive buffer (SO_RCVBUF) used by the socket server
socket.receive.buffer.bytes=102400
# The maximum size of a request that the socket server will accept (protection against OOM)
socket.request.max.bytes=104857600
############################# Log Basics #############################
# A comma separated list of directories under which to store log files
log.dirs=/tmp/kafka-logs
# The default number of log partitions per topic. More partitions allow greater
# parallelism for consumption, but this will also result in more files across
# the brokers.
num.partitions=1
# The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.
# This value is recommended to be increased for installations with data dirs located in RAID array.
num.recovery.threads.per.data.dir=1
############################# Internal Topic Settings #############################
# The replication factor for the group metadata internal topics "__consumer_offsets" and "__transaction_state"
# For anything other than development testing, a value greater than 1 is recommended to ensure availability such as 3.
offsets.topic.replication.factor=1
transaction.state.log.replication.factor=1
transaction.state.log.min.isr=1
############################# Log Flush Policy #############################
# Messages are immediately written to the filesystem but by default we only fsync() to sync
# the OS cache lazily. The following configurations control the flush of data to disk.
# There are a few important trade-offs here:
# 1. Durability: Unflushed data may be lost if you are not using replication.
# 2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.
# 3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to excessive seeks.
# The settings below allow one to configure the flush policy to flush data after a period of time or
# every N messages (or both). This can be done globally and overridden on a per-topic basis.
# The number of messages to accept before forcing a flush of data to disk
#log.flush.interval.messages=10000
# The maximum amount of time a message can sit in a log before we force a flush
#log.flush.interval.ms=1000
############################# Log Retention Policy #############################
# The following configurations control the disposal of log segments. The policy can
# be set to delete segments after a period of time, or after a given size has accumulated.
# A segment will be deleted whenever *either* of these criteria are met. Deletion always happens
# from the end of the log.
# The minimum age of a log file to be eligible for deletion due to age
log.retention.hours=168
# A size-based retention policy for logs. Segments are pruned from the log unless the remaining
# segments drop below log.retention.bytes. Functions independently of log.retention.hours.
#log.retention.bytes=1073741824
# The maximum size of a log segment file. When this size is reached a new log segment will be created.
log.segment.bytes=1073741824
# The interval at which log segments are checked to see if they can be deleted according
# to the retention policies
log.retention.check.interval.ms=300000
############################# Zookeeper #############################
# Zookeeper connection string (see zookeeper docs for details).
# This is a comma separated host:port pairs, each corresponding to a zk
# server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".
# You can also append an optional chroot string to the urls to specify the
# root directory for all kafka znodes.
zookeeper.connect=localhost:2181
# Timeout in ms for connecting to zookeeper
zookeeper.connection.timeout.ms=18000
############################# Group Coordinator Settings #############################
# The following configuration specifies the time, in milliseconds, that the GroupCoordinator will delay the initial consumer rebalance.
# The rebalance will be further delayed by the value of group.initial.rebalance.delay.ms as new members join the group, up to a maximum of max.poll.interval.ms.
# The default value for this is 3 seconds.
# We override this to 0 here as it makes for a better out-of-the-box experience for development and testing.
# However, in production environments the default value of 3 seconds is more suitable as this will help to avoid unnecessary, and potentially expensive, rebalances during application startup.
group.initial.rebalance.delay.ms=0
The Kafka-broker starts without a hitch with:
$ sudo bin/kafka-server-start.sh -daemon config/server.properties
I get the topic going with:
$ bin/kafka-topics.sh --bootstrap-server localhost:9092 --create --replication-factor 1 --partitions 1 --topic test
I then check with:
$ bin/kafka-topics.sh --bootstrap-server localhost:9092 --list
test
So I wonder where I messed up. BTW: The server is reachable from the client machine:
$ ping -c 5 10.0.0.20 -p 9092
PATTERN: 0x9092
PING 10.0.0.20 (10.0.0.20) 56(84) bytes of data.
64 bytes from 10.0.0.20: icmp_seq=1 ttl=64 time=0.468 ms
64 bytes from 10.0.0.20: icmp_seq=2 ttl=64 time=0.790 ms
64 bytes from 10.0.0.20: icmp_seq=3 ttl=64 time=0.918 ms
64 bytes from 10.0.0.20: icmp_seq=4 ttl=64 time=0.453 ms
64 bytes from 10.0.0.20: icmp_seq=5 ttl=64 time=0.827 ms
--- 10.0.0.20 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4095ms
rtt min/avg/max/mdev = 0.453/0.691/0.918/0.192 ms
