we are using Apache kafka 2.0 in our production environment and now we are planning to upgrade the kafka version to 2.6 from 2.0
we are running in three broker based cluster setup
i am having the below questions.
1)is it possible to upgrade the kafka from one version to higher version?
2)while upgrading is there any data loss happen?
3)is it possible to perform while the cluster is running?
4)How to rollback to the down version if something wrong happened?
can you share your valuable thoughts for this question..
it would be helpful to setup..
Yes, upgrades are possible - http://kafka.apache.org/26/documentation.html#upgrade
Data that's already written to the topics shouldn't get lost if you follow the guide. Active clients might experience network exceptions, retries, and potential dropped packets while individual brokers are restarting.
A rolling upgrade is possible to prevent downtime
Depending on the exact version, rollbacks are not possible due to internal log format changes (as indicated in the documentation)
Related
I am using kafka client & streams library version 2.7.0 for building my application. However the kafka brokers(2 different clusters) are at older version ( 2.4.1 & 2.6.0).
As i understand we can use the latest clients & Streams library and it should run fine with older version of kafka brokers. Am i correct ? Is there any compatibility matrix between client & streams library with kafka brokers ?
I tried running in my application (with 2.7.0 client library) in local environment ( with kafka version 2.6.0) and it worked fine but wanted to get the supported compatibility between them
Update: As onecricketeer has helpfully pointed out, you can refer to the Kafka Compatability Matrix. He also notes:
There is a general answer. Clients above 0.10.2 work with brokers down to that version for all basic functionality until stated otherwise. Extra functionality includes transactional/idempotence and record headers, which Spring may depend on, but Kafka Streams natively has no dependency on.
Additionally, the upgrade section of the Kafka Documentation provides guidance on upgrade order for various Kafka versions.
The compatability matrix provided by the spring-cloud-stream project may also be of assistance.
We are planning to upgrade Kafka broker to 2.12.X but our Kafka clients are still going to use 0.10.x or higher versions
On local, we have verified and not seen any issues in producing and consuming with older client versions mentioned above while the broker is upgraded to kafka_2.12-2.3.0
Is there a compatibility matrix for Kafka broker and client versions mentioned? Did anyone face any issues with such upgrades?
PS -
I went through below link
https://cwiki.apache.org/confluence/display/KAFKA/Compatibility+Matrix
As the link says, broker 1.0.0 (and up) will work for basic client interaction on any client that supports features added in KIP-35
The main missing features of clients before 0.11 or 1.0 would be the message headers and idempotent producer or exactly-once processing semantics for Kafka Streams
You'll also want to be careful on upgrading the log format version too soon, because as the Kafka upgrade steps say, you should only change that once most of the clients have upgraded
We are running an Apache Kafka 1.1.0 cluster with 5 brokers.
Since the machines are managed via Ansible, for us, the easiest way to update, would be rebuild the brokers one by one with the new version.
The main question is, can some brokers with 1.1.0 and some brokers with 2.3.0 coexist in the same cluster at the same time?
Although it is not the best practise, you can have brokers with different version in the same cluster. You'd have to configure inter.broker.protocol.version accordingly:
Specify which version of the inter-broker protocol will be used. This
is typically bumped after all brokers were upgraded to a new version.
Example of some valid values are: 0.8.0, 0.8.1, 0.8.1.1, 0.8.2,
0.8.2.0, 0.8.2.1, 0.9.0.0, 0.9.0.1 Check ApiVersion for the full list.
However, if the older and latest versions have a huge gap in-between, you might end up with compatibility (or other) issues.
"Upgrading from previous versions" section in Kafka docs, should shed some more light.
Should we update our Scala Kafka client library dependency (currently 0.10.2) to match the Kafka version of the broker (v1.1.0) ?
The Kafka 0.10.2 Documentation mentions
Starting with version 0.10.2, Java clients (producer and consumer)
have acquired the ability to communicate with older brokers. Version
0.10.2 clients can talk to version 0.10.0 or newer brokers
Are there any adverse effects when the client API version lags behind the server version? More importantly, can we safely update our Kafka client API library from 0.10.2 to 1.10?
While the brokers are now compatible with older clients, there are a few drawbacks in using older clients.
The main one is Message conversion. Between 1.1 and 0.10.2, the record format has changed. So, by default, older clients will force brokers to convert messages when producing and consuming. Conversion is pretty memory intensive and has a performance cost. See http://kafka.apache.org/documentation/#upgrade_11_message_format
Then obviously old clients are unable to use new features. Between 0.10.2 and 1.1, there's a ton a nice features like Exactly Once semantics, better authentication feedback on failure, Admin operations, etc
Currently, at my company we are migrating from Kafka 0.8 to 0.11, brokers migration steps and clearly stated in kafka documentation here
What I am stuck in is, upgrading the kafka clients (producers, consumers, spark-streaming), I don't find any documentation/ articles listing out clearly what are the required changes or steps to follow to upgarde the client, all what I found is the java doc Producer Client
What I did so far is to change the kafka client version in my gradle to kafka-clients-0.11.0.0, and everything from the compilation point of view went fine with no code changes at all.
What I seek help with is, is there any expected problems I should take care of, any pointers for client changes other than the kafka-client version?
I went through lots of experiments to get this done.
For the consumers and producers, I just used the kafka consumers and producers 0.11.0.
The trick part was replacing spark-streaming, spark-streaming latest version only support upto kafka 0.10.X, which doesn't contains any updates related to the new broker.
What I recommend here, if you are about to write an application from scratch and your main goal is realtime streaming go for kafka-streaming API, it is just AWESOME!, if you already have spark streaming app (which was my case), you should either judge which is more important than the other wether to get stuck with the kafka-broker version 10.X and spark-streaming which was [experimental][1] btw.
The benefits of having the streaming inside kafka not spark the following:
Kafka streaming is a normal jar that can be injected in any java application, so you don't care that much about deployment, and environment
Auto-scaling is so easy when using kafka-streaming using any scaleset provided by any cloud service provider, unlike scaling a HDP cluster.
Monitoring using something like prometheus would be much easier.