Questions about springboot redis (lettuce) health check - spring-boot

When using the Lettuce to connect redis cluster, if a slave node is unavailable, springboot health check will fails, but actually the read and write of the application are normal. Is this the design or a bug?
springboot: 2.3.12.RELEASE

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Access to Redis Cluster via Single Endpoint

I have a application using Redis. This system implemented with java spring used jedis package for connection to the redis with the configuration as follow
jedis.pool.host=redisServer-IP
so the application connect to redis server on the redisServer-IP and works fine but, for the lack of memory on a single server and and HA capability I need to use a redis cluster I used docker compose to create a redis cluster using the here.
Also redis cluster working fine with three masters and three replicas.
I just need to understand, the Redis Cluster can work with the single endpoint, because I can only set single endpoint in the above jedis.pool.host configuration, or I need to have a proxy to deal with the redis cluster ?
NOTE: I can not make any changes in my application

How to get Kafka brokers in a cluster using Spring Boot Kafka?

I have a Spring Boot (2.3.3) service using spring-kafka to currently access a dedicated Kafka/Zookeeper configuration. I have been using the application.properties setting spring.kafka.bootstrap-servers=localhost:9092 to access my dev/test Apache Kafka service.
However, in production, we have a Cluster of Kafka Brokers (on many servers) configured in Zookeeper, and I have been asked to modify my service to query Zookeeper to get the list of brokers and use that list instead of the bootstrap servers configuration. Reason, our DevOps folks have been known to reconfigure servers/nodes and Kafka brokers.
Basically, I have been asked to make my service agnostic to where the Apache Kafka brokers are running. All my service needs to know is how to get the list of brokers (bootstrap server info including host and port) from Zookeeper.
Is there a way in spring-boot and spring-kafka to retrieve from Zookeeper the broker list and use that broker (aka bootstrap server) list in my service?
Spring delegates to the kafka-clients for all connections; for a long time now, the kafka-clients no longer connect to Zookeeper, only to the brokers themselves.
There is no built-in support in Spring for querying the Zookeeper to determine the broker list.
Furthermore, in a future Kafka version, Zookeeper is going away altogether; see KIP-500.

Spring boot connect to alibaba e-mapreduce kafka

I'm trying to connect spring boot kafka app to kafka on alibaba cloud.
The cloud is on e-mapreduce service.
However, I can't connect from boot, maybe due to some security credential that I need to provide?
I've already tried to set the boot properties as follows:
spring.kafka.properties.security.protocol=SSL
Get error : Connection to node -1 (/xx.xx.xx.xx:9092) terminated during authentication. This may happen due to any of the following reasons: (1) Authentication failed due to invalid credentials with brokers older than 1.0.0, (2) Firewall blocking Kafka TLS traffic (eg it may only allow HTTPS traffic), (3) Transient network issue.
spring.kafka.properties.security.protocol=SASL_SSL
Throws Caused by: java.lang.IllegalArgumentException: Could not find a 'KafkaClient' entry in the JAAS configuration. System property 'java.security.auth.login.config' is not set
Anybody has experience connect to kafka on alibaba cloud?
I believe Kafka Connect could solve your problems of connect spring boot kafka app to kafka on Alibaba cloud:
Step 1: Create Kafka clusters
Create a source Kafka cluster and a target Kafka cluster in E-MapReduce.
Step 2: Create a topic for storing the data to be migrated
Create a topic named connect in the source Kafka cluster.
Step 3: Create a Kafka Connect connector
Use Secure Shell (SSH) to log on to the header node of the source Kafka cluster.
Optional:Customize Kafka Connect configuration.
Step 4: View the status of the Kafka Connect connector and task node
View the status of the Kafka Connect connector and task node and make sure that they are in normal status.
Follow other steps as your job needs are.
Detail instructions may be find on Use Kafka Connect to migrate data link: https://www.alibabacloud.com/help/doc-detail/127685.htm
Hope this will help you,

Spring Boot ZooKeeper client

I want to use ZooKeeper in order to synchronize my distributed services via ZooKeeper ephemeral nodes.
The idea is the following - every node in the topology on the startup will create ZooKeeper session and ephemeral nodes. On the node restart or failure, these nodes will disappear.
I'm going to implement it using Spring Boot. Right now I'm in doubt what project and Maven dependency to use in order to have ZooKeeper client autoconfiguration, be able to create ZooKeeper session on the application startup, be able to create from this client - ZooKeeper ephemeral nodes and use ZooKeeper transactions.
Right now I'm looking on Spring Cloud Zookeeper/ but I'm not sure is it a right one for this purpose. Could you please point me to the right Spring Boot ZooKeeper project and show the small example how to achieve that I have described above.

Know when Zookeeper connection is lost in a Springboot application

Is there a way to check whether zookeeper connection is lost while running Spring boot application ? After some research I came across health indicators from spring boot . But i cant find any article related to checking the health of the zookeeper connection from Spring boot. Or is there a simple,effective way out without using Health indicators ?
springboot has spring-cloud-zookeeper, it has ZookeeperHealthIndicator . if you use spring-cloud-zookeeper you do not need to care about it. or you can write your own zookeeper health indicator and take it as a reference.

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