I have a service fabric cluster with multiple microservices, and I want to set up Azure Front Door, however it asks for a healthcheck endpoint in the backend but I don't know how I am supposed to set it up since the cluster doesn't have an endpoint for that.
Could anyone point me in the right direction?
You could implement a health check on your service, by introducing a watchdog service. Optionally tapping into the built-in health system of SF. It could look like this:
Create an ASP .NET Core Web API, and implement some health checks. For example, a custom check if your SF Service is alive (and well). Here's how to get started. Return 200 OK from the API, if the watched SF Service is running correctly.
Run this Web API as an SF Service. Expose it through the Load Balancer.
Use its URL as the health endpoint for your Service(s).
Related
I don’t understand the difference between consul’s agent api and catalog api
Although the consul document has always emphasized that agent and catalog should not be confused，But there are indeed many methods that look similar, such as:
/catalog/services
/agent/services
When should I use catalog or agent（Just like the above http url）?
Which one is suitable for high frequency calls?
Consul is designed for services to be registered against a Consul client agent which is running on the same host where a service is deployed. The /v1/agent/service/ endpoints provide a way for you to interact with services which are registered with the specific Consul agent to which you are communicating, and register new services against that agent.
Each Consul agent in the data center submits its registered service information to the Consul servers. The servers aggregate this information to form the service catalog (https://www.consul.io/docs/architecture/anti-entropy#catalog). The /v1/catalog/ endpoints return that aggregated information.
I want to call out this sentence from the anti-entropy doc.
Consul treats the state of the agent as authoritative; if there are any differences between the agent and catalog view, the agent-local view will always be used.
The catalog APIs can be used to register or remove services/nodes from the catalog, but normally these operations should be performed against the client agents (using the /v1/agent/ APIs) since they are authoritative for data in Consul.
The /v1/agent/ APIs should be used for high frequency calls, and should be issued against the local Consul client agent running on the same node as the app, as opposed to communicating directly with the servers.
We're planning to develop some microservices based on the play framework. They will provide rest apis and lots of them will be using akka cluster/cluster-sharding under the hood.
We would like to have an api gateway that exposes the apis of our internal services, but we're facing one big issue:
- Multiple instances of each service will be running under some ip and port.
- How will the api gateway know where the services instances are running?
- Is there maybe something load-balancer-like for play that keeps track of all running services?
Which solution(s) could possibly fill the spot for the "API Gateway"/"Load Balancer"?
The question you're asking is not really related to play framework. And there is no single answer that would solve what you need.
You could start by reading akka Service Discovery and then make your choice based what fits you more.
We're building services with akka-http and use akka-cluster but use unrelated technologies to expose and run the services.
Check out
Kong for API Gateway
Consul for DNS based service discovery
docker swarm for running containers with mesh network for load balancing
You are looking for following components,
Service Registry : The whole point of this component is to keep track of "what service are running on what addresses". This can be as simple as a simple database which keeps entries for all the running services and their instances. Generally the orchestration service is responsible to register new service instances with Service Registry. Other choice can be to have instances themselves notify the service registry about their existence.
Service Health Checker : This component is mostly responsible for doing periodic runtime checks on the registered service instances and tell service registry if any of them is not working. The service registry implementation can then either mark these instances as "inactive" till they are found to be working by Service Health Checker in future (if ever).
Service Resolution : This is the conceptual component responsible for enabling a client to somehow get to the running service instances.
The whole of above components is called Service Discovery.
In your case, you have load-balancers which can act as a form of ServiceDiscovery.
I don't think load-balancers are going to change much over time unless you require a very advanced architecture, so your API gateway can simply "know" the url's to load-balancers for all your services. So, you don't really need service registry layer.
Now, your load-balancers inherently provide a health-check and quarantine mechanism for instances. So, you don't need an extra health check layer.
So, the only piece missing is to register your instances with the load balancer. This part you will have to figure out based on what your load-balancers are and what ecosystem they live in.
If you live in AWS ecosystem and your load balancers are ELB, then you should have things sorted out in that respect.
Based on Ivan's and Sarvesh's answers we did some research and discovered the netflix OSS projects.
Eureka can be used as service locator that integrates well with the Zuul api gateway. Sadly there's not much documentation on the configuration, so we looked further...
We've now finally choosen Kubernetes as Orchestator.
Kubernetes knows about all running containers, so there's no need for an external service locator like Eureka.
Traefik is an api gateway that utilizes the kuberentes api to discover all running microservices instances and does load balancing
Akka management finds all nodes via the kubernetes api and does the bootstrapping of the cluster for us.
Currently I'm working on a real-time online game. First I implemented a go server with socket.io for handling messages between client and my game world and it works fine. Now for user data managing I need a http api for some functionality like login. I want to use awesome http/net package for that purpose. Should I serve the http server on different Port?
My next question is for deploying I want to use google container engine. Can I use pods with two ports open?
As far as I understood from your explanation, you need two ports open for two different APIs running in your application. Regarding Exposing two ports in Google Container Engine, you can read the discussion here that describes ways to expose ports in a pod.
Moreover, I invite you read this tutorial that involves deploying an API in a GKE cluster with a containerPort in a pod, Creating a Kubernetes service to allow internal cluster traffic to your pods (routing requests on an incoming port to your API targetPort), and creating an Ingress service to define what traffic is allowed into your cluster and where it goes. You can define different APIs with different targetPorts and run them on different pods. You can try it as an alternative. For more documentation on Exposing Applications using Services, you can read this GKE doc.
I'm building a small web application for a personal project. It will be an Angular web application which will talk to a Spring-Boot service layer which in turn will read/write stuff to MongoDb.
I hope to host all this on a single EC2 instance in AWS. My question is how to configure a web server (like Apache but doesn't have to be) to 'beautify' the URLs a bit. Example, without touching anything angular will run at something like host:4200 and the service layer at host:8080. I will then have to map a proper domain to host in AWS, but the hiding of ports etc is where it gets murky for me.
I want to be able to hit my web app at domain.com (no ports etc) and I also want my service layer to ideally have a similar setup e.g. domain.com/service (no ports etc).
How do I configure a webservice to do this for me? Examples or pointers to specific examples would be ideal, but even a pointer to the right documentation will be helpful.
This thread is kind of similar to what I want but not too helpful: How to deploy Spring framework backend and Angular 2 frontend application in any online server?
You can use a setup with AWS CloudFront as reverse proxy and CDN cache. You can map the Domain Name and SSL Certificates(You can use AWS issued free SSL Certificates through AWS Certificate Manager) to CloudFront while the EC2 instance is plugged as an origin behind CloudFront as shown in the following diagram.
In the diagram I have optionally added, which is a common practice in designing applications in AWS.
Hosting the Angular App in S3
Using Autoscaling & Loadbalancing for EC2 instances.
You need to use Apache or other web server as a reverse proxy. Start here -
https://devops.profitbricks.com/tutorials/configure-apache-as-a-reverse-proxy-using-mod_proxy-on-ubuntu/
You then will need to setup a custom domain name. The easiest option is to just use an ELB (now called Classic Load Balancer). More details are here -
http://docs.aws.amazon.com/elasticloadbalancing/latest/classic/using-domain-names-with-elb.html
I'm interested in knowing if I can use Consul to solve the following issues:
1) Can Consul be used to load balance microservices? For instance, if I put console on the server that hosts my API gateway, can it be used to monitor all microservices it has discovered and load balance if I have two of the same microservice?
2) Can Consul be used at the microservice level to spin up instances as needed? Essentially, I'd like to not use IIS and find an alternative.
3) If for whatever reason Consul monitors a microservice as offline, can it attempt to start it up again? Or force a shut down of a microservice for whatever reason?
If Consul software can't solve these issues, is there other alternatives?
Thank you.
Consul DNS can provide a simple way for you to load balance services. It's especially powerful if you combine it with Consul Prepared Queries and health checks.
Consul is best suited for monitoring services (via health checks) but you can use consul watch to trigger events if a service suddenly becomes unavailable.
Hashicorp (the company behind Consul) offers another tool called Nomad.
Unlike Consul, Nomad is designed to run services (called jobs) and restart them if necessary.
Nomad works best if you tell it where to find Consul. This enables automatic service registration for any task Nomad launches, including deregistering it if you instruct Nomad to stop running that task. Health checks are supported as well.