I'm deploying a small Spring Cloud Stream project,
using only http sources and jdbc sinks (3 instances each). The estimated load is 10 hits/second.
I was thinking on using redis because I feel more confortable with it, but in the latest documentation almost all the refereces are to kafka and RabbitMQ so I am wondering if redis is not going to be supported in the future or if there is any issue using redis.
Regards
Redis is not recommended for production with Spring Cloud Stream - the binder is not fully functional and message loss is possible.
Related
We are currently trying to use Prometheus/Grafana in order to monitor several RabbitMQ instances deployed on multiple Docker containers.
My question is quite simple, what's the difference between using the Rabbitmq Prometheus Exporter vs Prometheus Plugin for RabbitMQ ?
Does the exporter scrape different/more information compared to the Plugin ?
Is there an overhead when using the Pluging compared to the exporter ?
Is it just a question of RabbiMQ's version ?
What is the added value from using one of the two options?
So basically what approach is better or can they be used in combination.
I have not trued out the plugin, but as far as I read it exports the same metrics as the exporter. The plugin has the advantage that it does not add complexity:
You need to host the rabbit exporter (which is not much effort, but still you need to make sure it runs, is updated from time to time,...)
You need an account for the rabbit exporter that can query the metrics which is a security issue. Your credentials might get stolen or the exporter might get compromised and and attacker would have access to your rabbit cluster.
Since there might be network between your rabbit cluster and the Rabbit exporter there might be the situation the exporter cannot reach the cluster while the plugin could still produce the metrics.
These are not big issues, we use the exporter for years now and never had an issue with it, but still, if we would start from scratch, we would give the plugin a try.
I've search for examples and I have not found any.
My intention is to use a Redis Stream as a source to Spring Cloud Dataflow and route messages to AWS Kinesis or S3 data sinks
Redis is not listed as a Spring Cloud Dataflow source. Will I have to create a custom binder?
Redis only seems available as a sink with PubSub
There used to be a redis-binder for Spring Cloud Stream, but that has been deprecated for a while now. We have plans to implement a binder for Redis Streams in the future, though.
That said, if you have data in Redis, it'd be good to start building a redis-source as a custom application. We have many suppliers/sources that you can use as a reference.
There's currently also a blog-series in the works, which can be of further guidance when building custom applications.
Lastly, feel free to contribute the redis-supplier/source to the applications repo, we can collaborate on a pull request.
For a large online application, use k8s to run it. The scale maybe daily activity user 500,000.
The application inside k8s need messaging feature - Pub/Sub, there are these options:
Kafka
RabbitMQ
Redis
Kafka
It needs zookeeper and good to run on os depends on disk I/O. So if install it into k8s cluster, how? The performance will be worse?
And, if keep Kafka outside of the k8s cluster, connect Kafka from application inside the k8s cluster, how about that performance? They are in the different layer, won't be slow?
RabbitMQ
It's slow than Kafka, but for a daily activity user 500,000 application, is it good enough? If so, maybe it's a good choice.
Redis
It's another option. Maybe the most simple one. But from the internet I got that it will lose message sometimes. If true, that's terrible.
So, the most important thing is, use Kafka(also with zookeeper) on k8s, good or not in this use case?
Yes, running Kafka on Kubernetes is great. Check out this example: https://github.com/Yolean/kubernetes-kafka. It includes ZooKeeper and Kafka as StatefulSets.
PS. Running any of the services in your question on Kubernetes will be pleasant. You can Google the name of the service and "kubernetes" and find example manifests. Many examples here: https://github.com/kubernetes/charts.
For Kafka, you can find some suggestion here. Kubernetes 1.7+ supports local persistent volume, which may be good for Kafka deployment.
You can also take a look to the following project :
https://github.com/EnMasseProject/barnabas
It's about running Kafka on Kubernetes and OpenShift as well. It provides deploying with StatefulSets with persistent volumes or just in memory (for developing or just testing purpose). It provides deploying for Kafka Connect and Prometheus metrics as well.
Another simple configuration of Kafka/Zookeeper on Kubernetes in DigitalOcean with external access:
https://github.com/StanislavKo/k8s_digitalocean_kafka
You can connect to Kafka from outside of AWS/DO/GCE by regular binary protocol. Connection is PLAINTEXT or SASL_PLAINTEXT (user/password).
Kafka cluster is StatefulSet, so you can scale cluster easily.
We're using spring cloud config server. Spring config clients get updates using spring control bus (RabbitMQ).
Looks like every config client instance creates a queue connected to the 'spring.cloud.bus' exchange.
Any scalability limits on how many app instances can connect to a 'spring.cloud.bus' exchange ?
I suppose RabbitMQ could be scaled to handle this.
Looking for any guidelines on this.
Many thanx,
The spring cloud config server can have multiple instances since it is stateless. That coupled with a RabbitMQ cluster should scale to a very large number of instances.
A viable solution would be spring cloud config behind a load balancer with a RabbitMQ cluster.
The Spring XD documentation (http://docs.spring.io/spring-xd/docs/1.0.0.RC1/reference/html/) recommends Zookeeper to be run in ensemble so that Zookeeper is highly available. There is not lot of details about Redis about high availability.
If I were to run 2 XD admin instances and say 4 Container instances, I see 3 options
should I run a Redis instance in each server that runs container or admin? In that case does the Distributed runtime work properly with different Redis instances handling transport of different modules?
OR
should I run 1 Redis instance in a separate server and configure all XD instances to talk to this instance? In this case 1 instance of Redis is not highly available
OR
should I configure Redis cluster or Redis Sentinel high availability? I am not sure how XD or any other client will connect to a cluster or HA.
Thanks
I would suggest that you run a single Redis instance, there are some settings for persistence that you can change that may meet your requirements.
http://redis.io/topics/persistence
We will be adding support for Redis Sentinal, certainly in the Spring XD 1.1 release, but possibly in a maintenance release depending on what library changes we need to pick up. Spring Data Redis and Spring Boot have recent updates to support Redis Sentinal.
If you are using Redis as a message transport and want higher guarantees, I would switch to using Rabbit HA configuration of the MessageBus.
Cheers,
Mark