We are looking to separate our blog platform to a separate ec2 server (In Nginx) for better performance and scalability.
Scenario is:
Web request (www.example.com) -> Load Balancer/Route -> Current EC2 Server
Blog request (www.example.com/blog) -> Load Balancer/Route -> New Separate EC2 Server for blog
Please help in this case what is the best option to use:
Haproxy
ALB - AWS
Any other solution?
Also, is it possible to have the load balancer or routing mechanism in a different AWS region? We are currently hosted in AWS.
Haproxy
You would have to set this up on an EC2 server and manage everything yourself. You would be responsible for scaling this correctly to handle all the traffic it gets. You would be responsible for deploying it to multiple availability zones to provide high availability. You would be responsible for installing all security updates on the operating system.
ALB - AWS
Amazon will automatically scale this out to handle any amount of traffic you get. Amazon will handle all security patches of the underlying system. Amazon provides free SSL certificates for ALBs. Amazon will deploy this automatically across multiple availability zones to provide high availability.
Any other solution?
I think AWS Global Accelerator would work here as well, but you would have to weigh the differences between Global Accelerator and ALB to decide which fits your use case and budget the best.
You could also look at placing a CDN in front of everything, like CloudFront or Cloudflare.
Also, is it possible to have the load balancer or routing mechanism in
a different AWS region?
AWS Global Accelerator would be the thing to look at if load balancing in different regions is a concern for you. Given the details you have provided I'm not sure why you would want this however.
Probably what you really need is a CDN in front of your websites, with or without the ALB.
Scenario is:
Web request (www.example.com) -> Load Balancer/Route -> Current EC2
Server Blog request (www.example.com/blog) -> Load Balancer/Route ->
New Separate EC2 Server for blog
In my view you can use ALB deployed in multi AZ for high availability for the following reasons :-
aws alb allows us to route traffic based on various attributes and path in URL is one of them them.
https://docs.aws.amazon.com/elasticloadbalancing/latest/application/load-balancer-listeners.html#rule-condition-types
With aws ALB you can have two target groups with instance handling traffic one for first path (www.example.com) and second target group for another path (www.example.com/blog).
ALB allows something called SNI (which allows to handle multiple certications behind a single alb for multiple domains), so all you need to do is set up single https listener and upload your certificates https://aws.amazon.com/blogs/aws/new-application-load-balancer-sni/
i have answered on [something similar] it might help you also
This is my opinion, take it as that. I am sure a lot of people wont agree.
If your project is small or personal, you can go with HAProxy (Cheap USD4 or less if you get a t3a as a spot instance) Or free if you place it inside another EC2 of yours may be using docker.
If your project is not personal or not small, go with ALB (Expensive but simpler and better integrated to other AWS stuff)
HAProxy can handle tons of connections, but you have to do more things by yourself. ALB can also handle tons of connections and AWS will do most of the work.
I think HAProxy is more suitable for personal/small projects because if your project doesnt grow, then you dont have to touch HAProxy. It is set and forget the same as ALB but cost less.
You usually wont mind about Availability zones or disaster tolerance in a personal project, so HAProxy should be easy to config.
Another consideration: AWS offers a free tier on ALB, so if your project will run for less than a year ALB is the way to go.
If you are learning, then ALB should be considered because real clients usually love to stick to AWS in all aspects, and HAProxy is your call and also your risk (just to reduce cost for a company that usually pays a lot more for your salary, so not worth the risk).
Related
Having a hard time figuring out a microservices architecture.
Right now I have an ECS Cluster with two services (TodoService, CategoriesService) running in containers. Both of the services have their own Load Balancer. I'm trying to build an API Gateway where /todos would route to the Todo-app-load-balancer and /categories would route to the Categories-app-load-balancer.
First, is this a good approach to microservices? And second, question from the title.
First, is this a good approach to microservices?
Yes, there is nothing wrong with this approach.
Can an API Gateway point to multiple Application Load Balancers?
Yes, you can point each method from the API gateway to an entirely different backend resource.
In case of an Application Load Balancer, there are multiple ways of doing this. Probably the easiest is to have a public Application Load Balancer and to create HTTP integration for it. You have to specify the DNS name for the application load balancer as the endpoint. For more information, see this support page.
Other option would be to use VPC Links, which would integration with private load balancers. While this would be recommended for production, it is a bit more complex to set it up.
Is it a good or bad approach is moreover an architectural decision, But I can suggest using one ALB(Ingress) with different rules can solve your problem, Also in API GATEWAY only allow to add ELB services directly ALB will not but still there is a workaround by adding direct DNS. Here I'm attaching two screenshots for your reference.
Direct integration is not allowed on ALB, but you can use the DNS name manually.
We have many internet services, what are the considerations whether to use alb per service or single alb for all using listener rule pointing to target 🎯 group.
The services has its own clusters/target group with different functionality and different url.
Can one service spike impact other services?
Is it going to be a single point of failure ?
Cost perspective ?
Observability, monitoring, logs ?
Ease of management ?
Personally I would normally use a single ALB and use different listeners for different services.
For example, I have service1.domain.com and service2.domain.com. I would have two hostname listeners in the same ALB which route to the different services.
In my experience ALB is highly available and scales very nicely without any issues. I've never had a service become unreachable due to scaling issues. ALB's scale based on "Load Balancer Capacity Units" (LBCU). As your load balancer requires more capacity, AWS automatically assigns more LBCU's which allows it to handle more traffic.
Source: Own experience working on an international system consisting of monoliths and microservices which have a large degree of scaling between timezones.
You don't have impact on service B if service A has a spike, but the identification of which service is having bad times could be a little pain.
For monitoring perspective it's is a bit hard because is not that easy to have a fast identification of which service/target is suffering.
For management, as soon as different teams need to create/management its targets it can create some conflicts.
I wouldn't encourage you using that monolith architecture.
From cost perspective you can use one load balancer with multi forward rules, but using a single central load balancer for an entire application ecosystem essentially duplicates the standard monolith architecture, but increases the number of instances to be served by one load balancer enormously. In addition to being a single point of failure for the entire system should it go down, this single load balancer can very quickly become a major bottleneck, since all traffic to every microservice has to pass through it.
Using a separate load balancer per microservice type may add additional overhead but it make single point of failure per microservice in this model, incoming traffic for each type of microservice is sent to a different load balancer.
I have simple server now (some xeon cpu hosted somewhere), running apache/php/mysql (no docker, but its a possibility) and Im expecting some heavy traffic and I need my server to handle that.
Currently the server can handle about 100 users at once, I need it to handle couple thousands possibly.
What would be easiest and fastest solution to move my app to some scalable hosting?
I have no experience with AWS or something like that.
I was reading about AWS and similar, but Im mostly confused and not sure what should I choose.
The basic choice is:
Scale vertically by using a bigger computer. However, you will eventually hit a limit and you will have a single-point of failure (one server!), or
Scale horizontally by adding more servers and spreading the traffic across the servers. This has the added advantage of handling failure because, if one server fails, the others can continue serving traffic.
A benefit of doing horizontal scaling in the cloud is the ability to add/remove servers based on workload. When things are busy, add more servers. When things are quiet, remove servers. This also allows you to lower costs when things are quiet (which is not possible on-premises when you own your own equipment).
The architecture involves putting multiple servers behind a Load Balancer:
Traffic comes into a Load Balancer
The Load Balancer sends the request to a server (often based upon some measure of how "busy" each server is)
The server processes the request and sends a response back to the Load Balancer
The Load Balancer sends the response to the original requester
AWS has several Load Balancers available, which vary by need. If you are simply sending traffic to a single application that is installed on all servers, a Network Load Balancer should be sufficient. For situations where different parts of the application are on different servers (eg mobile interface vs web interface), you could use a Application Load Balancer.
AWS also assists with horizontal scaling by providing the Amazon EC2 Auto Scaling service. This allows you to specify details of the servers to launch (disk image, instance type, network settings) and Auto Scaling can then automatically launch new servers when required and terminate ones that aren't required. (Note that they launch and terminate, not start and stop.)
You can further define scaling policies that tell Auto Scaling when to launch/terminate instances by measuring metrics such as CPU Utilization. This way, the number of servers can approximately match the volume of traffic.
It should be mentioned that if you have a database, it should be stored separately to the application servers so that it does not get terminated. You could use the Amazon Relational Database Service (RDS) to run a database for you, or you could run one on a separate Amazon EC2 instance.
If you want to find out more about any of the above technologies, there are plenty of talks on YouTube or blog posts that can explain and demonstrate their use.
The question might not be as fundamental as you thought. First of all, thanks for reading it. I am a computer science student. I just begin to learn about AWS, especially the Route 53 so please forgive me if there is anything that hurts your eyes :)
We all know that Amazon Route 53 provides customers with the ability
to route users to EC2 instances, S3 buckets, and elastic Load
Balancers across multiple availability zones and regions and there are
different forms of DNS load balancing including:
LBR/Latency Based Routing, to route to the region with the lowest latency
WRR/Weighted Round Robin, to assign weights to different targets
Also, user-specified configurations that combine both are possible
(LBR+WRR).
Route 53 flexibility allows users to save costs, however manual
configuration can become increasingly complex for final users. Looking
for the best non-probabilistic policy (such as the WRR weights) is
NP-complete.
What are the possible cases that we need to give server ip addresses different weight ? given that there can be EC2 servers that across multiple availability zones and instances can contain both front end and back end or contain either application tiers or databases only ? Are there any ideas of finding a possible better usage of Route 53 in combination with other AWS services, in order to improve the performance of interactive multi-tier cloud applications ?
Sorry for the lengthy question. I am looking for thoughts and ideas about the best way/starting point to experiment about the better usage of Route 53 and in combination with other AWS services for a multi-tier cloud application. Not necessarily a 100% correct answer. Any ideas or suggestions are welcomed. Many thanks in advance !
UPDATE:
I should probably rephrase the question: What is the purpose of having Weighted record set in Route 53 i.e in a DNS service ? Obviously, WRR in DNS can control potions of traffic but if we simply rely on this DNS load balance (or load distribution) we are going to put heavy workload on the many other DNS servers. One case I could think off is that web sites like google or Facebook will potentially gets tons of tons domain name queries, WRR DNS load balancing can be useful and there has to be some sort of session stickiness since sharing session across servers seems to be a bad idea.
Are there any other way / purpose of using Weighted record in Route 53.
Thank you very much for considering my question !
Another use case to consider is A/B testing of frontend or backend services. Let me illustrate: Let's say we've just CI-tested version 1.0.1 of our web application (which runs in a Docker container), and we've deployed the container but we're not yet routing traffic to it. We don't want to flip a switch and immediately dump our one million daily active users (woohoo!) onto v1.0.1 until we can give it a little real-world testing. So we decide to use the Weighted Round Robin load balancing available in Route 53 to send 0.25% of our users to the v1.0.1 container(s), allowing us to feel out the new version with real-world users before flipping the switch. We can do the same thing with virtually any service that uses hostname lookup to find resources.
One use case can be, to use it to load balance internal services that can't be balanced using an elastic load balancer, like a rds or elastic cache read replicas, so instead of creating a ec2 instance with a haproxy for example to load balance your services, you can create a Route 53 level balancer based on weights or latency.
My guess is that internally, they use a custom load balancer at the dns server, that balance requests based on domain aliases and the selected balancing policy.
Questions about load balancers if you have time.
So I've been using AWS for some time now. Super basic instances, using them to do some tasks whenever I needed something done.
I have a task that needs to be load balanced now. It's not a public service though. It's pretty much a giant cron job that I don't want running on the same servers as my website.
I set up an AWS load balancer, but it doesn't do what I expected it to do.
It get's stuck on one server, and doesn't load balance at all. I've read why it does this, and that's all fine and well, but I need it to be a serious round-robin load balancer.
edit:
I've set up the instances on different zones, but no matter how many instances I add to the ELB, it just uses one. If I take that instance down, it switches to a different one, so I know it's working. But I really would like it to always use a different one under every circumstance.
I know there are alternatives. Here's my question(s):
Would a custom php load balancer be an ok option for now?
IE: Have a list of servers, and have php randomly select a ec2 instance. Wouldn't be scalable at all, bu atleast I could set this up in 2 mins and it can work for now.
or
Should I take the time to learn how HAProxy works, and set that up in place of the AWS ELB?
or
Am I doing it wrong, and AWS's ELB does do round-robin. I just have something configured wrong?
edit:
Structure:
1) Web server finds a task to do.
2) If it's too large it sends it off to AWS (to load balancer).
3) Do the job on EC2
4) Report back via curl to an API
5) Rinse and repeat
Everything works great. But because the connection always comes from my server (one IP) it get's sticky'd to a single EC2 machine.
ELB works well for sites whose loads increase gradually. If you are expecting an uncommon and sudden increase on the load, you can ask AWS to pre-warm it for you.
I can tell you I used ELB in different scenarios and it always worked well for me. As you didn't provide too much information about your architecture, I would bet that ELB works for you, and the case that all connections are hitting only one server, I would ask you:
1) Did you check the ELB to see how many instances are behind it?
2) The instances that you have behind the ELB, are all alive?
3) Are you accessing your application through the ELB DNS?
Anyway, I took an excerpt from the excellent article that does a very good comparison between ELB and HAProxy. http://harish11g.blogspot.com.br/2012/11/amazon-elb-vs-haproxy-ec2-analysis.html
ELB provides Round Robin and Session Sticky algorithms based on EC2
instance health status. HAProxy provides variety of algorithms like
Round Robin, Static-RR, Least connection, source, uri, url_param etc.
Hope this helps.
This point comes as a surprise to many users using Amazon ELB. Amazon
ELB behaves little strange when incoming traffic is originated from
Single or Specific IP ranges, it does not efficiently do round robin
and sticks the request. Amazon ELB starts favoring a single EC2 or
EC2’s in Single Availability zones alone in Multi-AZ deployments
during such conditions. For example: If you have application
A(customer company) and Application B, and Application B is deployed
inside AWS infrastructure with ELB front end. All the traffic
generated from Application A(single host) is sent to Application B in
AWS, in this case ELB of Application B will not efficiently Round
Robin the traffic to Web/App EC2 instances deployed under it. This is
because the entire incoming traffic from application A will be from a
Single Firewall/ NAT or Specific IP range servers and ELB will start
unevenly sticking the requests to Single EC2 or EC2’s in Single AZ.
Note: Users encounter this usually during load test, so it is ideal to
load test AWS Infra from multiple distributed agents.
More info at the Point 9 in the following article http://harish11g.blogspot.in/2012/07/aws-elastic-load-balancing-elb-amazon.html
HAProxy is not hard to learn and is tremendously lightweight yet flexible. I actually use HAProxy behind ELB for the best of both worlds -- the hardened, managed, hands-off reliability of ELB facing the Internet and unwrapping SSL, and the flexible configuration of HAProxy to allow me to fine tune how things hit my servers. I've never lost an HAProxy instance yet, but it I do, ELB will just take that one out of rotation... as I have seen happen when the back-end servers have all become inaccessible, which (because of the way it's configured) makes ELB think the HAProxy is unhealthy, but that's by design in my setup.