Điểm:1

No connection to Kafka from Faust client

lá cờ pe

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
Điểm:1
lá cờ cn

Điều này có vẻ sai đối với tôi, vì nó có nghĩa là máy khách từ xa của bạn sẽ cố gắng kết nối với máy chủ cục bộ một khi nó được nói chuyện với máy chủ bootstrap, không phải địa chỉ từ xa của phiên bản kafka của bạn:

Advertisement.listeners=PLAINTEXT://localhost:9092

Tôi sẽ thay đổi nó thành IP bên ngoài (10.x.x.x) của phiên bản kafka của bạn, khởi động lại mọi thứ và thử lại.

ElToro1966 avatar
lá cờ pe
Đặt Advertisement.listeners thành 10.0.0.20 và thêm cổng 9092 vào các cổng được phép. Khởi động lại mọi thứ. Làm! Cảm ơn.

Đăng câu trả lời

Hầu hết mọi người không hiểu rằng việc đặt nhiều câu hỏi sẽ mở ra cơ hội học hỏi và cải thiện mối quan hệ giữa các cá nhân. Ví dụ, trong các nghiên cứu của Alison, mặc dù mọi người có thể nhớ chính xác có bao nhiêu câu hỏi đã được đặt ra trong các cuộc trò chuyện của họ, nhưng họ không trực giác nhận ra mối liên hệ giữa câu hỏi và sự yêu thích. Qua bốn nghiên cứu, trong đó những người tham gia tự tham gia vào các cuộc trò chuyện hoặc đọc bản ghi lại các cuộc trò chuyện của người khác, mọi người có xu hướng không nhận ra rằng việc đặt câu hỏi sẽ ảnh hưởng—hoặc đã ảnh hưởng—mức độ thân thiện giữa những người đối thoại.