I am running a microservice application off of AWS ECS. Each microservice currently has its own Load balancer.
There is one main public facing service which the rest of the services communicate with via gateways. Having each service have its own ELB is currently too expensive, is there some way to have only 1 ELB for the public facing service that will route to the other services based off of path. Is this possible without actually having the other service names in the URL. Could a reverse proxy work?
I know this is a broad question but any help would be appreciated
Inside your EC2 panel go to loadbalancers section, choose a loadbalancer and then in listeners tab, there is a button named view/edit rules, there you set conditions to use a single loadbalancer for different clusters/instances of your app. note that for each container you need a target group defined.
You can config loadbalancer to route based on:
Http Headers
Path i.e: www.example.com/a or www.example.com/b
Host Header(hostname)
Query strings
or even source Ip.
That's it! cheers.
Related
I am new to Google Cloud Platform and advanced networking in general but I have been tasked with setting up an external HTTPS load balancer that can forward internet traffic to 2 separate Virtual Machines on the same VPC. I have created the load balancer, SSL certs, DNS, frontend, and a backend. I have also created an instance group containing the two VM's for use with the backend.
What I am failing to understand is, how do I determine which VM is going to receive the traffic? Example:
I want test.com/login to go to instance1/some/path/login.php
I want test.com/download to go to instance2/some/path/file.script
Any help is greatly appreciated here. Thanks
To detail what #John Hanley mentioned in configuring URL maps, you can follow these steps :
On you load balancer balancer page. Click the name of the load balancer, then look for Edit.
Select Host and path rules, then click Add host and path rule.
On the host field, enter test.com/login. Then for your path, instance1/some/path/login.php.
Once done, for the Backends, select the backend associated to the VM instance. Do the same step for test.com/downloadby adding another host and path rule.
Click Update.
You can check and refer to this guide for more details
I am having hard time in understanding the role of a Load Balancer when used with Ingress Nginx.
I know a Load balancer distributes request over multiple nodes.
i.g, let's say I have two nodes A and B , and they are responisble for processing requests at example.com.
So a load balancer will take request for example.com and distribute among them with help of defined algorithm.
I also understand what an API Gateway is,
i.g., let's say I have one order service and another payment service so an API gateway will get the request for example.com and it will hand over the request for /orders to order service and /payments to payment service.
The Confusion:
Load Balancer(NLB) -> API Gateway -> Services -> order deployment -> which is running two replicas
Who distributes requests in those replicas for /orders
What is the role of load balancer in this case?
Some article suggest to create a service as type Load Balancer what does that mean? What this service will do?
Also, Load Balancer sits outside of the cluster NLB -> [ k8s cluster ], how does it know how to distribute requests?
These collectely could one question, I don't know.
Any kind of explanation would appreciated.
I have gone through many articles and blogs but none talks about complete picture.
Update
Many of my doubts are cleared through this article
Within the cluster a service does load balancing among the replicas.
Source
I still have some questions,
Do I only need a load balacner to expose the ingress controller service?
What if there is some problem with the ingress controller and it restarts.
What will happen will it get a new IP and load balancer will poin to new one or the ip will remain the same?
This article may help : https://aws.amazon.com/blogs/opensource/network-load-balancer-nginx-ingress-controller-eks/
Q: Do I only need a load balacner to expose the ingress controller service?
A: Expose K8s services mainly
Q: What if there is some problem with the ingress controller and it restarts.
A: Problem can appear if new broken changes will be applied, and in this case old controller will still work, but new one will fail to start, therefore you will have to do kubectl describe etc, to understand what is wrong.
Q: What will happen will it get a new IP and load balancer will poin to new one or the ip will remain the same?
A: Why you need LB ip's? Use LoadBalancer DNS.
I have a Node-Express website running on a microservices based architecture. I deployed the microservices on Amazon ECS cluster with one EC2 instance. The microservices sit behind an Application Load Balancer that routes external traffic correctly to the services. This system is working as expected except for one problem: I need to make a POST request from one service to the other. I am trying to use axios for this but I don't know what url to post to in axios. When testing locally, I just used axios.post('http://localhost:3000/service2',...) inside service 1 but how should I do it here?
So There are various ways.
1. Use Application Load Balancer behind the service
In this method, you put your micro services behind the load balancer(s) and to send request, you give load balancer URL. You can have path based routing for same load balancer or you can use multiple load balancers.
2. Use Service Discovery
In this method, you let your requester discover it. Now Service discovery can be done in various way like using ALB or Route 53 or ECS or Key Value Store or Configuration Management or Third Party Software such as Consul
If I have an ECS cluster with N distinct websites running as N services on said cluster - how do I go about setting up the load balancers?
The way I've done it currently is for each website X,
I create a new target group spanning all instances in the cluster
I create a new application load balancer
I attach the ALB to the service using the target group
It seems to work... but am want to make sure this is the correct way to do this
Thanks!
The way you are doing it is of course one way to do it and how most people accomplish this.
Application load balancers also support two other types of routing. Host based and path based.
http://docs.aws.amazon.com/elasticloadbalancing/latest/application/load-balancer-listeners.html#host-conditions
Host based routing will allow you to route based off of the incoming host from that website. So for instance if you have website1.com and website2.com you could send them both through the same ALB and route accordingly.
http://docs.aws.amazon.com/elasticloadbalancing/latest/application/load-balancer-listeners.html#path-conditions
Similarly you can do the same thing with the path. If you websites were website1.com/site1/index.html and website1.com/site2/index.html you could put both of those on the same ALB and route accordingly.
I am currently using Nginx server for my load balancer. But in order to use the Amazon's Load balancing feature I want to move to Amazon ELB. But the problem is my application has different routes or locations (same domain name with different sub-urls) that are handled by different ec2 instances. Like for example. (abc.com/ is handled by a set of ec2 instances while abc.com/xyz/* is handled by another set of instances). For now I use nginx to specify different upstream lists and and locations they handle. I tried to look at that in Amazon ELB but I didn't find it. So is it possible to do that in Amazon ELB or is there any way around that?
Sorry - other than supporting sticky sessions, there is no request-based routing logic in ELB.