Monday, February 24, 2025

Migrate from Commonplace brokers to Specific brokers in Amazon MSK utilizing Amazon MSK Replicator

Amazon Managed Streaming for Apache Kafka (Amazon MSK) now presents a brand new dealer kind referred to as Specific brokers. It’s designed to ship as much as 3 instances extra throughput per dealer, scale as much as 20 instances sooner, and scale back restoration time by 90% in comparison with Commonplace brokers operating Apache Kafka. Specific brokers come preconfigured with Kafka greatest practices by default, assist Kafka APIs, and supply the identical low latency efficiency that Amazon MSK clients anticipate, so you possibly can proceed utilizing current consumer functions with none modifications. Specific brokers present simple operations with hands-free storage administration by providing limitless storage with out pre-provisioning, eliminating disk-related bottlenecks. To study extra about Specific brokers, seek advice from Introducing Specific brokers for Amazon MSK to ship excessive throughput and sooner scaling to your Kafka clusters.

Creating a brand new cluster with Specific brokers is easy, as described in Amazon MSK Specific brokers. Nonetheless, in case you have an current MSK cluster, you have to migrate to a brand new Specific primarily based cluster. On this submit, we talk about how it is best to plan and carry out the migration to Specific brokers to your current MSK workloads on Commonplace brokers. Specific brokers supply a distinct person expertise and a distinct shared accountability boundary, so utilizing them on an current cluster shouldn’t be doable. Nonetheless, you should use Amazon MSK Replicator to repeat all knowledge and metadata out of your current MSK cluster to a brand new cluster comprising of Specific brokers.

MSK Replicator presents a built-in replication functionality to seamlessly replicate knowledge from one cluster to a different. It mechanically scales the underlying sources, so you possibly can replicate knowledge on demand with out having to observe or scale capability. MSK Replicator additionally replicates Kafka metadata, together with matter configurations, entry management lists (ACLs), and client group offsets.

Within the following sections, we talk about methods to use MSK Replicator to copy the information from a Commonplace dealer MSK cluster to an Specific dealer MSK cluster and the steps concerned in migrating the consumer functions from the outdated cluster to the brand new cluster.

Planning your migration

Migrating from Commonplace brokers to Specific brokers requires thorough planning and cautious consideration of varied elements. On this part, we talk about key points to deal with through the planning part.

Assessing the supply cluster’s infrastructure and desires

It’s essential to guage the capability and well being of the present (supply) cluster to ensure it could actually deal with further consumption throughout migration, as a result of MSK Replicator will retrieve knowledge from the supply cluster. Key checks embrace:

    • CPU utilization – The mixed CPU Consumer and CPU System utilization per dealer ought to stay beneath 60%.
    • Community throughput – The cluster-to-cluster replication course of provides additional egress visitors, as a result of it’d want to copy the prevailing knowledge primarily based on enterprise necessities together with the incoming knowledge. For example, if the ingress quantity is X GB/day and knowledge is retained within the cluster for two days, replicating the information from the earliest offset would trigger the whole egress quantity for replication to be 2X GB. The cluster should accommodate this elevated egress quantity.

Let’s take an instance the place in your current supply cluster you have got a median knowledge ingress of 100 MBps and peak knowledge ingress of 400 MBps with retention of 48 hours. Let’s assume you have got one client of the information you produce to your Kafka cluster, which implies that your egress visitors will probably be identical in comparison with your ingress visitors. Based mostly on this requirement, you should use the Amazon MSK sizing information to calculate the dealer capability you have to safely deal with this workload. Within the spreadsheet, you’ll need to offer your common and most ingress/egress visitors within the cells, as proven within the following screenshot.

As a result of you have to replicate all the information produced in your Kafka cluster, the consumption will probably be greater than the common workload. Taking this into consideration, your total egress visitors will probably be at the least twice the dimensions of your ingress visitors.
Nonetheless, once you run a replication software, the ensuing egress visitors will probably be greater than twice the ingress since you additionally want to copy the prevailing knowledge together with the brand new incoming knowledge within the cluster. Within the previous instance, you have got a median ingress of 100 MBps and you keep knowledge for 48 hours, which suggests that you’ve got a complete of roughly 18 TB of current knowledge in your supply cluster that must be copied over on high of the brand new knowledge that’s coming by. Let’s additional assume that your aim for the replicator is to catch up in 30 hours. On this case, your replicator wants to repeat knowledge at 260 MBps (100 MBps for ingress visitors + 160 MBps (18 TB/30 hours) for current knowledge) to catch up in 30 hours. The next determine illustrates this course of.

Subsequently, within the sizing information’s egress cells, you have to add an extra 260 MBps to your common knowledge out and peak knowledge out to estimate the dimensions of the cluster it is best to provision to finish the replication safely and on time.

Replication instruments act as a client to the supply cluster, so there’s a probability that this replication client can devour greater bandwidth, which might negatively influence the prevailing software consumer’s produce and devour requests. To manage the replication client throughput, you should use a consumer-side Kafka quota within the supply cluster to restrict the replicator throughput. This makes positive that the replicator client will throttle when it goes past the restrict, thereby safeguarding the opposite customers. Nonetheless, if the quota is ready too low, the replication throughput will undergo and the replication may by no means finish. Based mostly on the previous instance, you possibly can set a quota for the replicator to be at the least 260 MBps, in any other case the replication is not going to end in 30 hours.

  • Quantity throughput – Information replication may contain studying from the earliest offset (primarily based on enterprise requirement), impacting your major storage quantity, which on this case is Amazon Elastic Block Retailer (Amazon EBS). The VolumeReadBytes and VolumeWriteBytes metrics must be checked to ensure the supply cluster quantity throughput has further bandwidth to deal with any further learn from the disk. Relying on the cluster dimension and replication knowledge quantity, it is best to provision storage throughput within the cluster. With provisioned storage throughput, you possibly can improve the Amazon EBS throughput as much as 1000 MBps relying on the dealer dimension. The utmost quantity throughput might be specified relying on dealer dimension and kind, as talked about in Handle storage throughput for Commonplace brokers in a Amazon MSK cluster. Based mostly on the previous instance, the replicator will begin studying from the disk and the quantity throughput of 260 MBps will probably be shared throughout all of the brokers. Nonetheless, current customers can lag, which can trigger studying from the disk, thereby rising the storage learn throughput. Additionally, there may be storage write throughput on account of incoming knowledge from the producer. On this situation, enabling provisioned storage throughput will improve the general EBS quantity throughput (learn + write) in order that current producer and client efficiency doesn’t get impacted as a result of replicator studying knowledge from EBS volumes.
  • Balanced partitions – Be sure that partitions are well-distributed throughout brokers, with no skewed chief partitions.

Relying on the evaluation, you may must vertically scale up or horizontally scale out the supply cluster earlier than migration.

Assessing the goal cluster’s infrastructure and desires

Use the identical sizing software to estimate the dimensions of your Specific dealer cluster. Usually, fewer Specific brokers is perhaps wanted in comparison with Commonplace brokers for a similar workload as a result of relying on the occasion dimension, Specific brokers permit as much as 3 times extra ingress throughput.

Configuring Specific Brokers

Specific brokers make use of opinionated and optimized Kafka configurations, so it’s vital to distinguish between configurations which can be read-only and people which can be learn/write throughout planning. Learn/write broker-level configurations must be configured individually as a pre-migration step within the goal cluster. Though MSK Replicator will replicate most topic-level configurations, sure topic-level configurations are at all times set to default values in an Specific cluster: replication-factor, min.insync.replicas, and unclean.chief.election.allow. If the default values differ from the supply cluster, these configurations will probably be overridden.

As a part of the metadata, MSK Replicator additionally copies sure ACL varieties, as talked about in Metadata replication. It doesn’t explicitly copy the write ACLs besides the deny ones. Subsequently, when you’re utilizing SASL/SCRAM or mTLS authentication with ACLs somewhat than AWS Id and Entry Administration (IAM) authentication, write ACLs have to be explicitly created within the goal cluster.

Shopper connectivity to the goal cluster

Deployment of the goal cluster can happen inside the identical digital personal cloud (VPC) or a distinct one. Think about any modifications to consumer connectivity, together with updates to safety teams and IAM insurance policies, through the planning part.

Migration technique: Suddenly vs. wave

Two migration methods might be adopted:

  • Suddenly – All subjects are replicated to the goal cluster concurrently, and all shoppers are migrated directly. Though this method simplifies the method, it generates important egress visitors and includes dangers to a number of shoppers if points come up. Nonetheless, if there may be any failure, you possibly can roll again by redirecting the shoppers to make use of the supply cluster. It’s advisable to carry out the cutover throughout non-business hours and talk with stakeholders beforehand.
  • Wave – Migration is damaged into phases, shifting a subset of shoppers (primarily based on enterprise necessities) in every wave. After every part, the goal cluster’s efficiency might be evaluated earlier than continuing. This reduces dangers and builds confidence within the migration however requires meticulous planning, particularly for giant clusters with many microservices.

Every technique has its execs and cons. Select the one which aligns greatest with what you are promoting wants. For insights, seek advice from Goldman Sachs’ migration technique to maneuver from on-premises Kafka to Amazon MSK.

Cutover plan

Though MSK Replicator facilitates seamless knowledge replication with minimal downtime, it’s important to plan a transparent cutover plan. This consists of coordinating with stakeholders, stopping producers and customers within the supply cluster, and restarting them within the goal cluster. If a failure happens, you possibly can roll again by redirecting the shoppers to make use of the supply cluster.

Schema registry

When migrating from a Commonplace dealer to an Specific dealer cluster, schema registry concerns stay unaffected. Purchasers can proceed utilizing current schemas for each producing and consuming knowledge with Amazon MSK.

Answer overview

On this setup, two Amazon MSK provisioned clusters are deployed: one with Commonplace brokers (supply) and the opposite with Specific brokers (goal). Each clusters are positioned in the identical AWS Area and VPC, with IAM authentication enabled. MSK Replicator is used to copy subjects, knowledge, and configurations from the supply cluster to the goal cluster. The replicator is configured to keep up similar matter names throughout each clusters, offering seamless replication with out requiring client-side modifications.

Throughout the first part, the supply MSK cluster handles consumer requests. Producers write to the clickstream matter within the supply cluster, and a client group with the group ID clickstream-consumer reads from the identical matter. The next diagram illustrates this structure.

When knowledge replication to the goal MSK cluster is full, we have to consider the well being of the goal cluster. After confirming the cluster is wholesome, we have to migrate the shoppers in a managed method. First, we have to cease the producers, reconfigure them to jot down to the goal cluster, after which restart them. Then, we have to cease the customers after they’ve processed all remaining data within the supply cluster, reconfigure them to learn from the goal cluster, and restart them. The next diagram illustrates the brand new structure.

Migrate from Commonplace brokers to Specific brokers in Amazon MSK utilizing Amazon MSK Replicator

After verifying that every one shoppers are functioning accurately with the goal cluster utilizing Specific brokers, we are able to safely decommission the supply MSK cluster with Commonplace brokers and the MSK Replicator.

Deployment Steps

On this part, we talk about the step-by-step course of to copy knowledge from an MSK Commonplace dealer cluster to an Specific dealer cluster utilizing MSK Replicator and in addition the consumer migration technique. For the aim of the weblog, “suddenly” migration technique is used.

Provision the MSK cluster

Obtain the AWS CloudFormation template to provision the MSK cluster. Deploy the next in us-east-1 with stack identify as migration.

This can create the VPC, subnets, and two Amazon MSK provisioned clusters: one with Commonplace brokers (supply) and one other with Specific brokers (goal) inside the VPC configured with IAM authentication. It would additionally create a Kafka consumer Amazon Elastic Compute Cloud (Amazon EC2) occasion the place from we are able to use the Kafka command line to create and look at Kafka subjects and produce and devour messages to and from the subject.

Configure the MSK consumer

On the Amazon EC2 console, connect with the EC2 occasion named migration-KafkaClientInstance1 utilizing Session Supervisor, a functionality of AWS Methods Supervisor.

After you log in, you have to configure the supply MSK cluster bootstrap tackle to create a subject and publish knowledge to the cluster. You will get the bootstrap tackle for IAM authentication from the main points web page for the MSK cluster (migration-standard-broker-src-cluster) on the Amazon MSK console, below View Shopper Data. You additionally must replace the producer.properties and client.properties information to replicate the bootstrap tackle of the usual dealer cluster.

sudo su - ec2-user export BS_SRC=> sed -i "s/BOOTSTRAP_SERVERS_CONFIG=/BOOTSTRAP_SERVERS_CONFIG=${BS_SRC}/g" producer.properties  sed -i "s/bootstrap.servers=/bootstrap.servers=${BS_SRC}/g" client.properties

Create a subject

Create a clickstream matter utilizing the next instructions:

/residence/ec2-user/kafka/bin/kafka-topics.sh --bootstrap-server=$BS_SRC  --create --replication-factor 3 --partitions 3  --topic clickstream  --command-config=/residence/ec2-user/kafka/config/client_iam.properties

Produce and devour messages to and from the subject

Run the clickstream producer to generate occasions within the clickstream matter:

cd /residence/ec2-user/clickstream-producer-for-apache-kafka/ java -jar goal/KafkaClickstreamClient-1.0-SNAPSHOT.jar -t clickstream  -pfp /residence/ec2-user/producer.properties -nt 8 -rf 3600 -iam  -gsr -gsrr > -grn default-registry -gar

Open one other Session Supervisor occasion and from that shell, run the clickstream client to devour from the subject:

cd /residence/ec2-user/clickstream-consumer-for-apache-kafka/ java -jar goal/KafkaClickstreamConsumer-1.0-SNAPSHOT.jar -t clickstream  -pfp /residence/ec2-user/client.properties -nt 3 -rf 3600 -iam  -gsr -gsrr > -grn default-registry

Hold the producer and client operating. If not interrupted, the producer and client will run for 60 minutes earlier than it exits. The -rf parameter controls how lengthy the producer and client will run.

Create an MSK replicator

To create an MSK replicator, full the next steps:

  1. On the Amazon MSK console, select Replicators within the navigation pane.
  2. Select Create replicator.
  3. Within the Replicator particulars part, enter a reputation and optionally available description.

  1. Within the Supply cluster part, present the next data:
    1. For Cluster area, select us-east-1.
    2. For MSK cluster, enter the MSK cluster Amazon Useful resource Title (ARN) for the Commonplace dealer.

After the supply cluster is chosen, it mechanically selects the subnets related to the first cluster and the safety group related to the supply cluster. You too can choose further safety teams.

Ensure that the safety teams have outbound guidelines to permit visitors to your cluster’s safety teams. Additionally be sure that your cluster’s safety teams have inbound guidelines that settle for visitors from the replicator safety teams supplied right here.

  1. Within the Goal cluster part, for MSK cluster¸ enter the MSK cluster ARN for the Specific dealer.

After the goal cluster is chosen, it mechanically selects the subnets related to the first cluster and the safety group related to the supply cluster. You too can choose further safety teams.

Now let’s present the replicator settings.

  1. Within the Replicator settings part, present the next data:
    1. For the aim of the instance, we have now stored the subjects to copy as a default worth that might replicate all subjects from major to secondary cluster.
    2. For Replicator beginning place, we configure it to copy from the earliest offset, in order that we are able to get all of the occasions from the beginning of the supply subjects.
    3. To configure the subject identify within the secondary cluster as similar to the first cluster, we choose Hold the identical matter names for Copy settings. This makes positive that the MSK shoppers don’t want so as to add a prefix to the subject names.

    1. For this instance, we preserve the Shopper Group Replication setting as default (make certain it’s enabled to permit redirected shoppers resume processing knowledge from the final processed offset).
    2. We set Goal Compression kind as None.

The Amazon MSK console will mechanically create the required IAM insurance policies. In the event you’re deploying utilizing the AWS Command Line Interface (AWS CLI), SDK, or AWS CloudFormation, you must create the IAM coverage and use it as per your deployment course of.

  1. Select Create to create the replicator.

The method will take round 15–20 minutes to deploy the replicator. When the MSK replicator is operating, this will probably be mirrored within the standing.

Monitor replication

When the MSK replicator is up and operating, monitor the MessageLag metric. This metric signifies what number of messages are but to be replicated from the supply MSK cluster to the goal MSK cluster. The MessageLag metric ought to come all the way down to 0.

Migrate shoppers from supply to focus on cluster

When the MessageLag metric reaches 0, it signifies that every one messages have been replicated from the supply MSK cluster to the goal MSK cluster. At this stage, you possibly can lower over consumer functions from the supply to the goal cluster. Earlier than initiating this step, verify the well being of the goal cluster by reviewing the Amazon MSK metrics in Amazon CloudWatch and ensuring that the consumer functions are functioning correctly. Then full the next steps:

  1. Cease the producers writing knowledge to the supply (outdated) cluster with Commonplace brokers and reconfigure them to jot down to the goal (new) cluster with Specific brokers.
  2. Earlier than migrating the customers, be sure that the MaxOffsetLag metric for the customers has dropped to 0, confirming that they’ve processed all current knowledge within the supply cluster.
  3. When this situation is met, cease the customers and reconfigure them to learn from the goal cluster.

The offset lag occurs if the patron is consuming slower than the speed the producer is producing knowledge. The flat line within the following metric visualization exhibits that the producer has stopped producing to the supply cluster whereas the patron hooked up to it continues to devour the prevailing knowledge and ultimately consumes all the information, subsequently the metric goes to 0.

  1. Now you possibly can replace the bootstrap tackle in properties and client.properties to level to the goal Specific primarily based MSK cluster. You will get the bootstrap tackle for IAM authentication from the MSK cluster (migration-express-broker-dest-cluster) on the Amazon MSK console below View Shopper Data.
export BS_TGT=> sed -i "s/BOOTSTRAP_SERVERS_CONFIG=.*/BOOTSTRAP_SERVERS_CONFIG=${BS_TGT}/g" producer.properties sed -i "s/bootstrap.servers=.*/bootstrap.servers=${BS_TGT}/g" client.properties

  1. Run the clickstream producer to generate occasions within the clickstream matter:
cd /residence/ec2-user/clickstream-producer-for-apache-kafka/ java -jar goal/KafkaClickstreamClient-1.0-SNAPSHOT.jar -t clickstream  -pfp /residence/ec2-user/producer.properties -nt 8 -rf 60 -iam  -gsr -gsrr > -grn default-registry -gar

  1. In one other Session Supervisor occasion and from that shell, run the clickstream client to devour from the subject:
cd /residence/ec2-user/clickstream-consumer-for-apache-kafka/ java -jar goal/KafkaClickstreamConsumer-1.0-SNAPSHOT.jar -t clickstream  -pfp /residence/ec2-user/client.properties -nt 3 -rf 60 -iam  -gsr -gsrr > -grn default-registry

We will see that the producers and customers at the moment are producing and consuming to the goal Specific primarily based MSK cluster. The producers and customers will run for 60 seconds earlier than they exit.

The next screenshot exhibits producer-produced messages to the brand new Specific primarily based MSK cluster for 60 seconds.

Migrate stateful functions

Stateful functions reminiscent of Kafka Streams, KSQL, Apache Spark, and Apache Flink use their very own checkpointing mechanisms to retailer client offsets as an alternative of counting on Kafka’s client group offset mechanism. When migrating subjects from a supply cluster to a goal cluster, the Kafka offsets within the supply will differ from these within the goal. Consequently, migrating a stateful software together with its state requires cautious consideration, as a result of the prevailing offsets are incompatible with the goal cluster’s offsets. Earlier than migrating stateful functions, it’s essential to cease producers and be sure that client functions have processed all knowledge from the supply MSK cluster.

Migrate Kafka Streams and KSQL functions

Kafka Streams and KSQL retailer client offsets in inside changelog subjects. It’s advisable to not replicate these inside changelog subjects to the goal MSK cluster. As an alternative, the Kafka Streams software must be configured to start out from the earliest offset of the supply subjects within the goal cluster. This permits the state to be rebuilt. Nonetheless, this methodology ends in duplicate processing, as a result of all the information within the matter is reprocessed. Subsequently, the goal vacation spot (reminiscent of a database) have to be idempotent to deal with these duplicates successfully.

Specific brokers don’t permit configuring phase.bytes to optimize efficiency. Subsequently, the inner subjects have to be manually created earlier than the Kafka Streams software is migrated to the brand new Specific primarily based cluster. For extra data, seek advice from Utilizing Kafka Streams with MSK Specific brokers and MSK Serverless.

Migrate Spark functions

Spark shops offsets in its checkpoint location, which must be a file system appropriate with HDFS, reminiscent of Amazon Easy Storage Service (Amazon S3). After migrating the Spark software to the goal MSK cluster, it is best to take away the checkpoint location, inflicting the Spark software to lose its state. To rebuild the state, configure the Spark software to start out processing from the earliest offset of the supply subjects within the goal cluster. This can result in re-processing all the information from the beginning of the subject and subsequently will generate duplicate knowledge. Consequently, the goal vacation spot (reminiscent of a database) have to be idempotent to successfully deal with these duplicates.

Migrate Flink functions

Flink shops client offsets inside the state of its Kafka supply operator. When checkpoints are accomplished, the Kafka supply commits the present consuming offset to offer consistency between Flink’s checkpoint state and the offsets dedicated on Kafka brokers. Not like different programs, Flink functions don’t depend on the __consumer_offsets matter to trace offsets; as an alternative, they use the offsets saved in Flink’s state.

Throughout Flink software migration, one method is to start out the applying and not using a Savepoint. This method discards your complete state and reverts to studying from the final dedicated offset of the patron group. Nonetheless, this prevents the applying from precisely rebuilding the state of downstream Flink operators, resulting in discrepancies in computation outcomes. To handle this, you possibly can both keep away from replicating the patron group of the Flink software or assign a brand new client group to the applying when restarting it within the goal cluster. Moreover, configure the applying to start out studying from the earliest offset of the supply subjects. This allows re-processing all knowledge from the supply subjects and rebuilding the state. Nonetheless, this methodology will lead to duplicate knowledge, so the goal system (reminiscent of a database) have to be idempotent to deal with these duplicates successfully.

Alternatively, you possibly can reset the state of the Kafka supply operator. Flink makes use of operator IDs (UIDs) to map the state to particular operators. When restarting the applying from a Savepoint, Flink matches the state to operators primarily based on their assigned IDs. It is suggested to assign a novel ID to every operator to allow seamless state restoration from Savepoints. To reset the state of the Kafka supply operator, change its operator ID. Passing the operator ID as a parameter in a configuration file can simplify this course of. Restart the Flink software with parameter --allowNonRestoredState (if you’re operating self-managed Flink). This can reset solely the state of the Kafka supply operator, leaving different operator states unaffected. Consequently, the Kafka supply operator resumes from the final dedicated offset of the patron group, avoiding full reprocessing and state rebuilding. Though this may nonetheless produce some duplicates within the output, it ends in no knowledge loss. This method is relevant solely when utilizing the DataStream API to construct Flink functions.

Conclusion

Migrating from a Commonplace dealer MSK cluster to an Specific dealer MSK cluster utilizing MSK Replicator supplies a seamless, environment friendly transition with minimal downtime. By following the steps and techniques mentioned on this submit, you possibly can reap the benefits of the high-performance, cost-effective advantages of Specific brokers whereas sustaining knowledge consistency and software uptime.

Able to optimize your Kafka infrastructure? Begin planning your migration to Amazon MSK Specific brokers in the present day and expertise improved scalability, velocity, and reliability. For extra particulars, seek advice from the Amazon MSK Developer Information.


Concerning the Creator

Subham Rakshit is a Senior Streaming Options Architect for Analytics at AWS primarily based within the UK. He works with clients to design and construct streaming architectures to allow them to get worth from analyzing their streaming knowledge. His two little daughters preserve him occupied more often than not exterior work, and he loves fixing jigsaw puzzles with them. Join with him on LinkedIn.

Related Articles

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Latest Articles