We are get many errors from server.log from each of 3 kafka machines ( we have 3 kafka in the cluster )
[2019-12-05 13:25:09,529] ERROR [ReplicaFetcherThread-0-1], Error for partition [jdty.dee.rules.time,91] to broker 1001:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2019-12-05 13:25:09,529] ERROR [ReplicaFetcherThread-0-1], Error for partition [jdty.dee.export.profiles,96] to broker 1001:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2019-12-05 13:25:09,529] ERROR [ReplicaFetcherThread-0-1], Error for partition [jdty.dee.control.tt.state,40] to broker 1001:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2019-12-05 13:25:09,529] ERROR [ReplicaFetcherThread-0-1], Error for partition [jdty.dee.control.tt,67] to broker 1001:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
from my understanding each topic is served by one or multiple Brokers - one is leader and the remaining brokers are followers.
A producer needs to send new messages to the leader Broker which internally replicate the data to all followers.
I assume, that your producer client does not connect to the correct Broker, its connect to a follower instead of the leader, and this follower rejects your send request.
so my question is - how to configure the producer configuration in order to avoid such these errors?
Follower brokers fetch from the leader broker (the leader is not pushing to followers). Hence, it seems that a follower broker tries to fetch from the wrong (leader) broker. This can happen is the leader of a partition changed. The corresponding follower broker should update its cluster metadata automatically to rediscover the new leader. If the error persists, it indicates that this follower broker has issues to update its metadata.
Related
I have 5 broker kafka version 0.10 cluster.Replication factor is 3. and this is production kafka
brokers IDS are
101
102
103
104
105
after couple months that cluster was ok , we observed following logs in Kakfa server.log.
from the log we can see many lines of 'This server is not the leader for that topic-partitionb' exception.
the topic - kopa.thrn.bvff have 100 partitions
and we can see that all 100 partitions are balanced and no need to run kafka kafka-reassign-partitions
What may be the possible reason?
Please help me.
[2023-01-19 11:53:37,434] ERROR [ReplicaFetcherThread-0-101], Error for partition [kopa.thrn.bvff,78] to broker 101:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2023-01-19 11:53:37,434] ERROR [ReplicaFetcherThread-0-101], Error for partition [kopa.thrn.bvff,23] to broker 101:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2023-01-19 11:53:37,434] ERROR [ReplicaFetcherThread-0-101], Error for partition [kopa.thrn.bvff,63] to broker 101:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2023-01-19 11:53:37,434] ERROR [ReplicaFetcherThread-0-101], Error for partition [kopa.thrn.bvff,98] to broker 101:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
[2023-01-19 11:53:37,434] ERROR [ReplicaFetcherThread-0-101], Error for partition [kopa.thrn.bvff,3] to broker 101:org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition. (kafka.server.ReplicaFetcherThread)
The leader broker and the follower brokers manage each partition in Kafka. Since you have replication factor 3, each partition will have one leader broker and 2 follower brokers.
When the Kafka producer produces data, it connects to the leader and puts the data there, the followers will copy the data from the leader.
Now, the Kafka leader broker can be reassigned based on the leader's availability, if the leader was unavailable for some time for any reason in a distributed environment (busy CPU, network partition etc), Kafka will run the leader election for the partition to elect a leader for the partition.
You can see who is the leader and who is the follower by topic describe command.
In your case, the partition leader has been changed due to some unavailability of the leader. If you have Kafka metrics, you could see those leader election events for the partition. It is hard in a distributed environment to ensure one broker will remain the leader forever.
I notice the message in kafka broker logs
Partition <topic name> marked as failed (kafka.server.ReplicaFetcherThread)
My question is how and when does Kafka mark a partition as failed.
I need to monitor the logs and take action on messages.
Is this message actionable or something that can be ignored?
I have been creating a Kafka Producer example using Java. I have been
sending normal data which is just "Test" + Integer as value to Kafka. I
have used the below properties and after I have started the Producer
Client and messages are on the way, during this I am killing the broker
and suddenly receiving the below error message instead of retrying.
Using 3 brokers and topic with 3 partitions and replication factor as 3
and no min-insync-replicas
Below are the properties configured config.put(ProducerConfig.ACKS_CONFIG, "all");
config.put(ProducerConfig.MAX_IN_FLIGHT_REQUESTS_PER_CONNECTION, "1");
config.put(CommonClientConfigs.RETRIES_CONFIG, 60);
config.put(ProducerConfig.ENABLE_IDEMPOTENCE_CONFIG, true);
config.put(ProducerConfig.RETRY_BACKOFF_MS_CONFIG ,10000);
config.put(ProducerConfig.REQUEST_TIMEOUT_MS_CONFIG ,30000);
config.put(ProducerConfig.MAX_BLOCK_MS_CONFIG ,10000);
config.put(ProducerConfig.MAX_REQUEST_SIZE_CONFIG , 1048576);
config.put(ProducerConfig.BATCH_SIZE_CONFIG, 16384);
config.put(ProducerConfig.LINGER_MS_CONFIG, 0);
config.put(ProducerConfig.BUFFER_MEMORY_CONFIG, 1073741824); // 1GB
and the result when I have killed all my brokers or sometimes one of the
broker is as below
**Error:**
WARN org.apache.kafka.clients.producer.internals.Sender - [Producer
clientId=producer-1] Got error produce response with correlation id 124
on topic-partition testing001-0, retrying (59 attempts left). Error:
NETWORK_EXCEPTION
27791 [kafka-producer-network-thread | producer-1] WARN
org.apache.kafka.clients.producer.internals.Sender - [Producer
clientId=producer-1] Received invalid metadata error in produce request
on partition testing001-0 due to
org.apache.kafka.common.errors.NetworkException: The server disconnected
before a response was received.. Going to request metadata update now
28748 [kafka-producer-network-thread | producer-1] ERROR
org.apache.kafka.common.utils.KafkaThread - Uncaught exception in thread
'kafka-producer-network-thread | producer-1':
java.lang.OutOfMemoryError: Java heap space
at java.nio.HeapByteBuffer.<init>(Unknown Source)
at java.nio.ByteBuffer.allocate(Unknown Source)
at org.apache.kafka.common.memory.MemoryPool$1.tryAllocate
(MemoryPool.java:30)
at org.apache.kafka.common.network.NetworkReceive.readFrom
(NetworkReceive.java:112)
at org.apache.kafka.common.network.KafkaChannel.receive
(KafkaChannel.java:335)
at org.apache.kafka.common.network.KafkaChannel.read
(KafkaChannel.java:296)
at org.apache.kafka.common.network.Selector.attemptRead
(Selector.java:560)
at org.apache.kafka.common.network.Selector.pollSelectionKeys
(Selector.java:496)
at org.apache.kafka.common.network.Selector.poll(Selector.java:425)
at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:510)
at org.apache.kafka.clients.producer.internals.Sender.run
(Sender.java:239)
at org.apache.kafka.clients.producer.internals.Sender.run
(Sender.java:163)
at java.lang.Thread.run(Unknown Source)
I assume you are testing the producer. When a producer connect to the Kafka cluster you will pass all broker IPs and ports as a comma separated string. In your case there are three brokers. When producer try to connect to cluster, as part of initialization cluster controller responds with cluster metadata. Assume your producer only populating message to a single topic. Cluster maintains a leader among brokers for each and every topic. After identify the leader for the topic, your producer only going to communicate to the leader until it is live.
In your testing scenario, you are deliberately killing the broker instances. When it happens kafka cluster need to identify a new leader for your topic and controller has to pass the new meta data to your producer. If the metadata change quite frequently( in your case you may kill another broker mean while) producer may receive invalid metadata.
We have 5 kafka 1.0.0 clusters:
4 of them are made of 3 nodes and are in different regions in the world
the last one is made of 5 nodes and is an aggregate only cluster.
We are using MirrorMaker (later referenced as MM) to read from the regional clusters and copy the data in the aggregate cluster in our HQ datacenter.
And not sure about where to run it we have currently 2 cases in our prod environment:
MM in the region: reading locally and pushing to aggregate cluster in remote data-center (DC), before committing offsets locally. I tend to call this the push mode (pushing the data)
MM in the DC of the aggregate cluster: reading remotely the data, writing it locally before committing the offsets on remote DC.
What happened is that we got the entire DC where we have our aggregate server totally isolated from a network point of view. And in both cases, we got duplicated records in our aggregate cluster.
Push mode = MM local to the regional cluster, pushing data to remote aggregate cluster
MM started to throw errors like this:
WARN [Producer clientId=producer-1] Got error produce response with correlation id 674364 on topic-partition <topic>-4, retrying (2147483646 attempts left). Error: NETWORK_EXCEPTION (org.apache.kafka.clients.producer.internals.Sender)
then:
WARN [Producer clientId=producer-1] Connection to node 1 could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
which is ok so far because of idempotence.
But finally we got errors like:
ERROR Error when sending message to topic debug_sip_callback-delivery with key: null, value: 1640 bytes with error: (org.apache.kafka.clients.producer.internals.ErrorLoggingCallback)
org.apache.kafka.common.errors.TimeoutException: Expiring 1 record(s) for <topic>-4: 30032 ms has passed since batch creation plus linger time
ERROR Error when sending message to topic <topic> with key: null, value: 1242 bytes with error: (org.apache.kafka.clients.producer.internals.ErrorLoggingCallback)
java.lang.IllegalStateException: Producer is closed forcefully.
causing MM to stop and I think this is the problem causing duplicates (I need to dig the code, but could be that it lost information about idempotence and on restart it resumed from previously committed offsets).
Pull mode = MM local to the aggregate cluster, pulling data from remote regional cluster
MM instances (with logs at INFO level in this case) started seeing the broker as dead:
INFO [Consumer clientId=mirror-maker-region1-agg-0, groupId=mirror-maker-region1-agg] Marking the coordinator kafka1.region1.internal:9092 (id: 2147483646 rack: null) dead (org.apache.kafka.clients.consumer.internals.AbstractCoordinator)
At the same time on the broker side, we got:
INFO [GroupCoordinator 1]: Member mirror-maker-region1-agg-0-de2af312-befb-4af7-b7b0-908ca8ecb0ed in group mirror-maker-region1-agg has failed, removing it from the group (kafka.coordinator.group.GroupCoordinator)
...
INFO [GroupCoordinator 1]: Group mirror-maker-region1-agg with generation 42 is now empty (__consumer_offsets-2) (kafka.coordinator.group.GroupCoordinator)
Later on MM side, a lot of:
WARN [Consumer clientId=mirror-maker-region1-agg-0, groupId=mirror-maker-region1-agg] Connection to node 2 could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
and finally when network came back:
ERROR [Consumer clientId=mirror-maker-region1-agg-0, groupId=mirror-maker-region1-agg] Offset commit failed on partition <topic>-dr-8 at offset 382424879: The coordinator is not aware of this member. (org.apache.kafka.clients.consumer.internals.ConsumerCoordinator)
i.e., it could not commit in region1 the offsets written on agg because of the rebalancing. And it resumed after rebalance from previously successfully committed offset causing duplicates.
Configuration
Our MM instances are configured like this:
For our consumer:
bootstrap.servers=kafka1.region1.intenal:9092,kafka2.region1.internal:9092,kafka3.region1.internal:9092
group.id=mirror-maker-region-agg
auto.offset.reset=earliest
isolation.level=read_committed
For our producer:
bootstrap.servers=kafka1.agg.internal:9092,kafka2.agg.internal:9092,kafka3.agg.internal:9092,kafka4.agg.internal:9092,kafka5.agg.internal:9092
compression.type=none
request.timeout.ms=30000
max.block.ms=60000
linger.ms=15000
max.request.size=1048576
batch.size=32768
buffer.memory=134217728
retries=2147483647
max.in.flight.requests.per.connection=1
acks=all
enable.idempotence=true
Any idea how we can get the "only once" delivery on top of exactly once in case of 30 min isolated DCs?
I was running my services that work with kafka already for a year and no spontaneous changes of leader happens.
But for the last 2 weeks that started happens quite often.
Kafka log on that:
[2015-09-27 15:35:14,826] INFO [ReplicaFetcherManager on broker 2]
Removed fetcher for partitions [myTopic] (kafka.server.ReplicaFetcherManager)
[2015-09-27 15:35:14,830] INFO Truncating log myTopic-0 to offset 11520979. (kafka.log.Log)
[2015-09-27 15:35:14,845] WARN [Replica Manager on Broker 2]: Fetch request with correlation id 713276 from client ReplicaFetcherThread-0-2 on partition [myTopic,0] failed due to Leader not local for partition [myTopic,0] on broker 2 (kafka.server.ReplicaManager)
[2015-09-27 15:35:14,857] WARN [Replica Manager on Broker 2]: Fetch request with correlation id 256685 from client mirrormaker-1 on partition [myTopic,0] failed due to Leader not local for partition [myTopic,0] on broker 2 (kafka.server.ReplicaManager)
[2015-09-27 15:35:20,171] INFO [ReplicaFetcherManager on broker 2] Removed fetcher for partitions [myTopic,0] (kafka.server.ReplicaFetcherManager)
What can cause switching leader? If there is info in some kafka documentation - please - just point the link. I've failed to find.
System configuration
kafka version: kafka_2.10-0.8.2.1
os: Red Hat Enterprise Linux Server release 6.5 (Santiago)
server.properties (differs from default):
broker.id=001
socket.send.buffer.bytes=1048576
socket.receive.buffer.bytes=1048576
socket.request.max.bytes=104857600
log.flush.interval.messages=10000
log.flush.interval.ms=1000
log.retention.bytes=-1
controlled.shutdown.enable=true
auto.create.topics.enable=false
It appears like lead broker is down for that partition. It might be that data directroy(log.dirs) configured in server.properties is out of space and broker is not able to accommodate.
Also, what is replication factor of topic and cluster size of brokers?
I am assuming you have one topic and one partition with a replication factor of 2. Which is not a good configuration for optimal Kafka performance and consumers.
Your Logs are not clear enough for leader switch. Major issue in your topic may be having the only one leader due to the only partition. Now the single file in your logs is getting bigger in size day by day. Kafka internally does rebalancing at some level(details are not confirmed). That can be the reason for your leader switch. But i am not sure.
Also in your 2nd log line its says some of the logs are truncated. Can you please go though the logs in details and check is this happening only after truncation?
As you already mentioned you already checked your Kafka log directory files and their size. Please run the describe when you got this issue. The leader switch will reflect here as well. Or if you can setup some dashboard that will display the leader for past time. Then it will be easy for you to find the root cause.
bin/kafka-topics.sh --describe --zookeeper Zookeeperhost:Port --topic TopicName
Suggestion: i will suggest you to create a new topic with more partitions(read Kafka documentation to get a good idea about optimum number of partitions) and start writing to it. Or you can check, how to change partitions for current topic.
Last Thing: Is leader switch causing some issues in your Clients or you are worried only about warnings?