My design has:
1 React based FrontEnd.
1 NodeJS RestAPI split into 2 microservices. (1 manages 3 endpoints about mailing and the other manages all the other functions).
The FrontEnd always talk to the main microservice and when needed the main microservice send tasks to the mailing microservice using a RabittMQ "topic" queue.
There is also a MongoDB database.
This works good in docker in my dev machine altogether.But I want this to be easily scalable, so I would like to use kubernetes.
What would be a good design approach for having 3 frontends, 2 main microservices and 1 mailing microservice? I must use a single cluster in order to get RabbitMQ working? Is there an obvious better alternative than RabbitMQ now that i plan to use kubernetes?
Real world companies use AWS "solved" services or just get an EC2 machine and install everything like i plan to do to save costs while i learn?
Related
Lets say I have 5 Microservices and each microservice has 3 instances each. To deploy these microservices Do we need 15 different servers to deploy each Microservice ???
So In large scale application Let's say i have 100 Microservice and each microservice has 3 instance running in that case i need 300 servers to deploy each microservice's instances??
Please correct me on this
There is nothing like that 1 MicroService Instance = 1 Physical Server.
Microservice means that service only knows about its presense and its own data.
If some other service want to give some task to another service they have to call that service via endpoint for example Http or via bus.
By saying this you can have a one big server and that can have all the services.
If you want all the services belong to one instance or for one customer can be in one server, it is also possible.
In this area, you have to compute how much resource required by each service and its instance and that will be the driving factor in deciding this strategy.
CONTEXT: I have been learning Kubernetes and trying to get some hands-on experience. I have been using AKS to abstract the complexity of having to deal with the control plane (and because I have a free student azure account). I am deploying a NodeJS app that connects to the MongoDB database. So far the deployment has been successful but I am using MongoDB Atlas and connecting to it.
Based on the little I have learned about Stateful sets, the MongoDB Atlas service seems a lot easier and more convenient but my question is, when would it be a better idea to consider deploying a stateful set with MongoDB database? (running on the pod) What's more cost-effective? More easily scalable?
I realize the questions might be a little bit vague but I am just getting started with Kubernetes..
disclaimer: This is not a production application, just something simple I am using to learn K8S
Official docs docs uses statefullset and that would make sense. Generally all DB kind of applications deployed as statefullset. Because there can be states that nodes are not sync with each other and that would create data inconsistencies between nodes(mongodb nodes not kubernetes).
You can deploy MongoDB as deployment. I have seen it deployed. But most clients use a connection string to connect(a string of multiple node addresses). And since kubernetes exposes statefullsets with headless services you should be okay.
For learning purpose, I advice you to deploy your MongoDB in a StatefulSet. Then you can learn how it works and what problem you could encounter with this Kubernetes object.
For production application, I advice to never deploy a database in a StatefulSet if you don't need it. In fact, StatefulSet will come with a lot of problematics that you might not need to manage.
Sometimes, companies rules restrict to host their data on external company storage.
To know if you need to put your database in a StatefulSet, the question I try to answer is:
Should my DB be hosted on premise (for privacy)?
Should my DB be scalable?
Should my DB be updated frequently?
You can find a list of pros/cons on the documentation.
I deploying a python + tensorflow + flask application using a fully managed Google Cloud Run Service (1 vCPUs and 4 GB Ram).
System works fine but it is really slow, so I am evaluating ways of making it fast (it needs to run 20-30 times faster than what is doing now)
What would be the best approach?
To use a Kubernetes Cluster with one or two powerful machines
To use a Kubernetes Cluster with 3-5 weaker machines
To forget about Kubernets/Docker and run everything on single powerfull VM
Something else maybe?
For now I don't expect to have more than 10 users at a time but I want to be able to scale it up eventually.
You might want to evaluate according to your use case
Per this article, Fully managed Cloud Run is an ideal serverless platform for stateless containerized microservices that don’t require Kubernetes features like namespaces, co-location of containers in pods (sidecars) or node allocation and management.
GKE is a great choice if you are looking for a container orchestration platform that offers advanced scalability and configuration flexibility.
You mentioned you are looking the cheaper/easier method to develop, but this will probably not be as scalable, efficient or manageable, you might want to take a closer look at all cloud compute options in GCP to see what could benefit your use case the most.
You mentioned your use case is CPU intensive, so you might want to leverage the high CPU machine types, these might be used directly by creating a VM, creating an instance group or using them in other services like GKE or App Engine
Is it a good practice to setup Elasticsearch, logstash and kiban on 3 different servers, with each server having RAM of 8GB.
Or
Setup ELK on 1 single machine with higher memory of 16GB.
The machine needs to be highly available.
Can anyone suggest or share inputs
it depends on your task and situation. normally it is good practice to setup Elasticsearch, logstash and kiban on 3 different server. or if you data if more so you have to make a cluster of elastic search or may have more than one server of logstash .
filefeats will be on all the data(log) server .
there are an example of handling 25000 logs per secoung
https://engineering.viki.com/blog/2015/log-processing-at-scale-elk-cluster-at-25k-events-per-second/
Its slightly more complicated than explained here,
Any distributed component would try to offer features with sharded or partioned way. In a similar way the Elastic Search at ELK which is based out of Master Slave model and maintains the data at ES data nodes. This means one needs to set up a cluster of nodes for Elastic search itself for its various components such as ES Master, ES data and ES client.
The next level if the system is required at production grade which requires Multi master setup with minimum 3 master nodes.
This would be the beginning of ELK.
If one needs to run such a complex system in a limited resources, then Containerizing the ELK components and running them in a container orchestration framework is the recommended option. Kubernetes/Docker swarm are the options to run ELK cluster based on the dockerized instances of ELK. Again these orchestration frameworks also require multimaster setup , but that would be fair as one would have lot more components in a cloud environment and all of them could be controlled under these orchestration frameworks.
I want to know if it is possible to run kafka as a cloud-native application, and can I create a kafka cluster as a service on Pivotal Web Services. I don't want only client integration, I want to run the kafka cluster/service itself?
Thanks,
Anil
I can point you at a few starting points, there would be some work involved to go from those starting points to something fully functional.
One option is to deploy the kafka cluster on Cloud Foundry (e.g. Pivotal Web Services) using docker images. Spotify has Dockerized kafka and kafka-proxy (including Zookeeper). One thing to keep in mind is that PWS currently doesn't support apps with persistence (although this work is starting) so if you were to go this route right now, you would lose the data in kafka when the application is rolled. Looking at that Spotify repo, it looks like the docker images are generally run without any mounted volumes, so this persistence-less kafka seems like it may be a valid use case (I don't know enough about kafka to say).
The other option is to deploy kafka directly on some IaaS (e.g. AWS) using BOSH. BOSH can be hard if you're seeing it for the first time, but it is the ideal way to deploy any distributed software that you want running on VMs. You will also be able to have persistent volumes attached to your kafka VMs if necessary. Here is a kafka BOSH release which may work.
Once you have your cluster running, you have two ways to integrate your Cloud Foundry applications with it. The simplest is just to provide it to your applications as a "user-provided service", which lets you flow kafka cluster access info to your apps. The alternative would to put a service broker in front of your cluster, which would be especially useful if you have many different people who will be pushing apps that need to talk to the kafka cluster. Rather than you having to manually tell people the access info each time, they can do something simple like cf bind-service SOME_APP YOUR_KAFKA_SERVICE. Here is a kafka service broker along with more info about service brokers in general.
According to the 12-factor app description (https://12factor.net/processes), Kafka should not run as an application on top of Cloud Foundry:
Twelve-factor processes are stateless and share-nothing. Any data that needs to persist must be stored in a stateful backing service, typically a database.
Kafka is often considered a "distributed commit log" and as such carries a large amount of state. Many companies use it to keep all events flowing through their distributed system of micro services for a long (sometimes unlimited) amount of time.
Therefore I would strongly recommend to go for the second option in the accepted answer: Kafka topics should be bound to your applications in the form of stateful services.