the need: I have a team of people who are not particularly tech savvy but we still want them to be able to access a jupyter notebook in a hosted ec2 instance (which has got access to a variety of resources in AWS). Not all of the people use this instance all the time but it's reasonable to believe that that the instance will be used continuosly by one person or the other throughout the day ( and we do not have budget to scale up things on demand).
the solution: to use a single medium sized instance in a multi-tenant fashion so that basically every user could link up to it and, as more users connect, resources are re-distributed (meaning the already present users will witness reduced capacity in RAM and CPU - up to a limit as CPUs are finite in number) and, as they disconnect, the opposite happens.
the problem & question: I saw there are some pretty beefy/complicated infrastructure designs for this. my question is: what's the simplest (=least complicated/expensive to maintain solution) architecture to cater such need?
p.s. on security: all users are equal, there are not users who have got more rights than others, instance will be accessible just via a pwd, no ID management is required.
p.s. on caching sessions: after a certain period of inactivity (or you close down the browser in this case), session will be terminated on its own. no session caching needs to be employed
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I have made a Business Card ordering portal and its backend is in NodeJS.
I am currently using t2.micro and I am getting like 50 daily users and 15-20 concurrent users but in some time the user count would go up to 300 daily users and 100 concurrent users. I don't want to spend much either.
It has single database and we don't use threads.
I am confused whether I should change my instance type or should use Auto Scaling Groups.
I am not a pro in AWS. Please help!!
Nobody can give you an answer to your question because every application is different.
Some applications need more CPU (eg for encoding/encrypting). Some need lots of RAM (for calculations). Some need lots of disk access (eg for file manipulation).
Only you know how your application behaves and what resources it would need.
You could either pick something and then monitor it (CPU, RAM, Disk) in production to see where the 'bottleneck' lies, or you could create a test that simulates the load of users and pushes it to breaking point to discover the bottleneck.
I am trying to find the best way to architect a low cost solution to provide an on-demand web server for a certain amount of time.
The context is as follows: I have some large amount of data sitting on S3. From time to time, users will want to consult that data. I've written a Flask app that can display the data in a nice way for them. Beign poorly written, it really only accepts a single user session at the time. Currently therefore they have to download the Flask app and run it on their own machine.
I would like to find a way for users to request a cloud-based web server that would run the Flask app (through a docker container for example) on-demand, and give them access to it quickly, without having to do much if anything on their own machine.
Every user wanting to view the data would have their own web server created on demand (to avoid multiple users sharing the same web server, which wouldn't work with my Flask app)
Critically, and in order to avoid cost, the web server would terminate itself automatically after some (configurable) idle time (possibly with the Flask app informing the user that it's about to shut down, so that they can "renew" the lease).
Initially I thought that maybe AWS Fargate would be good: it can run docker instances, is quite configurable in terms of CPU/disk it can get (my Flask app is resource-hungry), and at least on paper could be used in a way that there is zero cost when users are not consulting the data (bar S3 costs naturally). But it's when it comes to the detail that I'm not sure...
How to ensure that every new user gets their own Fargate instance?
How to shut-down the instance automatically after idle time?
Is Fargate quick enough in terms of boot time?
The closest I can think is AWS App Runner. It's built on top of Fargate and it provides an intelligent scale out mechanism (probably you are not interested in this) as well as a scale to (almost) 0 capability. The way it works is that when the endpoint is solicited and it's doing work you pay for the entire fargate task (cpu/memory) you have selected in the configuration. If the endpoint is doing nothing you only pay for the memory (note the memory cost is roughly 20% of the entire cost so it's not scale to 0 but "quasi"). Checkout the pricing examples at the bottom of this page.
Please note you can further optimize costs by pausing/starting the endpoint (when it's paused you pay nothing) but in that case you need to create the logic that pauses/restarts it.
Another option you may want to explore is using Lambda this way (which would allow you to use the same container image and benefit from the intrinsic scale to 0 of Lambda). But given your comment "Lambda doesn’t have enough power, and the timeout is not flexible" may be a show stopper.
I've been trying to wrap my head around the best solution for hosting development sites for our company lately.
To be completely frank I'm new to AWS and it's architecture, so more then anything I just want to know if I should keep learning about it, or find another more suitable solution.
Right now we have a dedicated server which hosts our own website, our intranet, and a lot of websites we've developed for clients.
Our own web and the intranet isn't an issue, however I'm not quite sure about the websites we produced for our clients.
There are about 100 of them right now, these sites are only used pre-launch so our clients can populate the sites with content. As soon as the content is done we host the website somewhere else. And the site that is still on our developer server is no longer used at all, but we keep them there if the client wants a new template/function so we can show it there before sending it to production.
This means the development sites have almost zero traffic, with perhaps at most 5 or so people adding content to them at any given time (5 people for all 100 sites, not 5 per site).
These sites needs to be available at all times, and should always feel snappy.
These are not static sites, they all require a database connection.
Is AWS (ES2, or any other kind of instance, lightsail?) a valid solution for hosting these sites. Or should I just downgrade our current dedicated server to a VPS, and just worry about hosting our main site on AWS?
I'll put this in an answer because it's too long, but it's just advice.
If you move those sites to AWS you're likely to end up paying (significantly) more than you do now. You can use the Simple Monthly Calculator to get an idea.
To clarify, AWS is cost-effective for certain workloads. It is cost effective because it can scale automatically when needed so you don't have to provision for peak traffic all the time. And because it's easy to work with, so it takes fewer people and you don't have to pay a big ops team. It is cost effective for small teams that want to run production workloads with little operational overhead, up to big teams that are not yet big enough to build their own cloud.
Your sites are development sites that just sit there and see very little activity. Which means those sites are probably under the threshold of cost effective.
You should clarify why you want to move. If the reason is that you want as close to 100% uptime as possible, then AWS is a good choice. But it will cost you, both in terms of bill paid to Amazon and price of learning to set up such infrastructure. If cost is a primary concern, you might want to think it over.
That said, if your requirements for the next year or more are predictable enough and you have someone who knows what they are doing in AWS, there are ways to lower the cost, so it might be worth it. But without further detail it's hard for anyone to give you a definitive answer.
However. You also asked if you should keep learning AWS. Yes. Yes, you should. If not AWS, one of the other major clouds. Cloud and serverless[1] are the future of much of this industry. For some that is very much the present. Up to you if you start with those dev sites or something else.
[1] "Serverless" is as misleading a name as NoSQL. It doesn't mean no servers.
Edit:
You can find a list of EC2 (Elastic Cloud Compute) instance types here. That's CPU and RAM. Realistically, the cheapest instance is about $8 per month. You also need storage, which is called EBS (Elastic Block Store). There are multiple types of that too, you probably want GP2 (General Purpose SSD).
I assume you also have one or more databases behind those sites. You can either set up the database(s) on EC2 instance(s), or use RDS (Relational Database Service). Again, multiple choices there. You probably don't want Multi-AZ there for dev. In short, Multi-AZ means two RDS instances so that if one crashes the other one takes over, but it's also double the price. You also pay for storage there, too.
And, depending on how you set things up you might pay for traffic. You pay for traffic between zones, but if you put everything in the same zone traffic is free.
Storage and traffic are pretty cheap though.
This is only the most basic of the basics. As I said, it can get complicated. It's probably worth it, but if you don't know AWS you might end up paying more than you should. Take it slow and keep reading.
You'll have to excuse my ignorance on this one...but honestly, I've had a hard time finding clarity on this. That being said, I'm looking for a non technical answer...something in layman's terms!
Anyways, I've been playing around building a web app (first time obviously) and I'm getting to the point where I've started looking into hosting services. A quick google search and a few blogs later, I thought AWS would be a good place to start, since they give a free-year trial. I don't care about speedy upstarts or other hosting serves, so save your key strokes on offering other services.
My question is based on the fact that AWS charges "Linux Usage per hour" and they also use this term "instance". Yeah...an "instance" is an "object", which is also above my head (probably the real source of the problem), but that was the extent I was able to learn via a google search. That being said, I don't know how to translate the cost into a ball park cost. Yes, I can probably use the trial to help monitor predictable costs, but I don't want to go through the effort of learning one hosting companies system just to find out it's not going to work in the end.
OK...so hopefully by now you see where I'm coming from. What is an "instance" and how do I use the "Linux Usage per hour" to estimate cost? Is an instance a server? For example if I start NGINX is that in instance? Is it just one instance running NGINX or does every VPN represent an instance? If I have 100 people calling the server at once, can they fit on one instance? If I start another server say, Apache or Node, does that become another instance? If I connect to a database, is that an instance? Do instances start as needed? Yes, I know, that's more than one question...I'm just trying to express my confusion.
If I'm suppose to choose a pricing model from this list, "Linux Usage per hour", I need to know what them mean by "Linux Usage". If it's based on an "instance", I need to know what that is. So please, in layman's terms, help clear this up. Maybe some examples or analogies, but no deep technical stuff.
This is more a side note, but I was reading this article and it said
For a client needing to run 800 virtual instances, the annual cost of
a private cloud came to below $400,000 vs. somewhere between $800,000
and $1.2 million for public cloud services.
Considering I don't know what an instance is, that kinda made me a bit nervous...WAAAAAAyyyyyy outta my price range! Yes, it's obviously a big company, but can you imagine "hitting the lottery" with an app everyone loves then before you know it, AWS hits you with a bill of $1,000,000. Or even worse, your security sucks and someone spawns millions of these "instances"...help alive my paranoia!!
Basically, an instance is a virtual machine, which looks very much like a server. As such it's running an operating system - e.g. linux - which is capable of running many programs (aka 'processes' or sometimes, 'services') at the same time.
To go through your questions (some of the explanations below are not technically accurate, but are hopefully more explanatory for it - if anything is obvious or already known, apologies - trying not to assume any knowledge)
An instance is an object
This definition is coming up in your searches because 'instance' has many definitions in different situations. If you see the definition of 'instance' as an object, it's from the topic of object oriented programming languages - you define a class in your code (kind of like a 'template'), and then create instances of the class - kind of like real copies of the template.
Amazon borrowed the term to be analogous - because in the 'cloud' world, you can create an AMI (Amazon Machine Image - the template) and then create lots of instances that are copies or clones of that template.
Is an instance a server?
In terms of what you can do with it, yes, it's a server.
(Technically it's a virtual server - Amazon runs multiple virtual servers on each physical server.)
how do I use the "Linux Usage per hour" to estimate cost?
Estimate how long you will have your instance running for in hours per month, multiply it by cost per hour and you will have your estimated cost per instance per month.
e.g. - one instance always turned on would be - 24 hrs * 31 days = 744 hours. At $0.013/hr (for a t2.micro) that would be 744 * $0.013 = $9.672/mth.
(And that's the reason the free tier gives you 750 hours of instance time per month.)
Instances come in different types and sizes and each size costs a different amount. If you are not sure what size you need, I'd start with the smallest until you discover you need more - which would be when your program starts running too slowly.
For example if I start NGINX is that in instance?
Nginx is a program that runs as a daemon in linux terms - a program that runs in the background so it's always on. It will be one of the many programs running on the server (aka the instance)
If I have 100 people calling the server at once, can they fit on one instance?
It depends - on how big your instance is, and how efficient the program is that is responding to their requests. If you are just getting started learning to program websites, I wouldn't worry about handling 100 people issuing requests to the server all at once just yet - walk before you run :) (also, even when there are 100 people visiting your website, the odds that all of them issue a request at exactly the same time is low - usually they load a page and read it - while they're reading it, some of the other people are loading other pages, and it all spreads out so you might only have ~10 page requests actively being processed by your server at the same time.)
However, if you have 2,000 people on your site at the same time, you might be processing 200 page requests at once, so by then you do need to have put some thought into performance and scalability.
(Note: these numbers are arbitrary and depend entirely on the type of site and it's traffic patterns.)
Generally, most websites pick a mid-level instance size, and then to handle more requests they 'scale out' - create lots of copies of that instance, and allow each instance to handle a portion of the traffic.
If I start another server say, Apache or Node, does that become another instance
The language to use here would be 'start another service say, Apache or Node' - they are other programs, and your instance will be perfectly fine running nginx, apache and node all at the same time. Although each will consume some of the resources (e.g. memory and cpu) and the more activity they are doing, the faster you will run out of resources and need to get a bigger instance size
So - no, they don't automatically become another instance. The language is confusing because sometimes people don't distinguish between the 'server' (aka the instance) and the service (aka the program) and will say the 'apache server' and the 'apache service' interchangably.
If I connect to a database, is that an instance?
Your instance, as a fully capable server, could run a database service on it at the same time as the other services - e.g. you could install and run mysql on your instance.
There is another option, though - if you use the AWS RDS product, then you will be starting an RDS instance. An RDS instance is different from an EC2 instance (what we've been talking about so far) in that RDS instances are specialised to just run the database service and nothing else, but EC2 instances are general servers that you can do pretty much anything on.
It's usually recommended to use RDS, but if you are trying to save money and aren't serving many users, there's nothing particularly wrong with installing mysql on your instance yourself (especially while you're learning how it works) and then moving your data to an RDS instance when you want to support more load or traffic.
Do instances start as needed?
Not by default, no - you have to manually start and stop them.
However, there are options other than manually starting and stopping. Amazon provides a lot of APIs, so you could write a program that would connect to the API and automatically start and stop your instance(s) based on rules you build into your program..
Also, Amazon offers a product called "AutoScalingGroups" which allows you to have a related group of instances and for Amazon to automatically start and stop them according to rules that you configure into that product. These rules can be 'scheduled actions' - start/stop at certain times of day - or they can be reactive - e.g. when the average CPU usage is > 50% for more than 5 minutes, start another instance.
This is more a side note, but I was reading this article and it said
For a client needing to run 800 virtual instances, the annual cost of
a private cloud came to below $400,000 vs. somewhere between $800,000
and $1.2 million for public cloud services.
The 'free tier' gives you a t2.micro sized instance (1 vCPU, 1 GiB RAM) which you could leave turned on permanently for free during that free year.
Even after your free tier expires, that same instance would cost you $9.67/mth, and you have the option to go downgrade to a t2.nano (0.5 GiB RAM) which would only cost ~$4/mth - but 0.5GiB RAM isn't much these days, so may not be enough for you.
A t2.micro should be more than enough to learn how to build websites on. If you are fortunate enough to build a site that is popular enough that you are getting more requests than that server can handle, then you will have to decide if you can generate revenue from that popularity sufficient to cover the cost, but by then you'll have more of a sense of how efficient your program is, and what instance size (and/or how many instances) you'll need.
Yes, it's obviously a big company, but can you imagine "hitting the
lottery" with an app everyone loves then before you know it, AWS hits
you with a bill of $1,000,000
AWS protects you from yourself here a bit - they have limits which generally restrict you from running more than 20 instances at a time - unless you ask for permission. So, by default, your instance won't go multiplying like rabbits on it's own - unless you set it up to. And even if you have set it up to, it won't be able to grow beyond 20 instances unless you have asked amazon to let you. So, worst case is 20 x $9.67/mth - $197/mth.
But - that's just the instance cost. Amazon charges you for lots of things including data traffic in and out, RDS instance costs, and if you start using other service such as S3 buckets and/or elastic load balancers, they all attract their own costs.
But hopefully, if you hit the lottery with an app everyone loves, you've worked out how to convert that love into dollars and cents so you can pay for all those instances you're going to need :)
I was contracted to make a groupon-clone website for my client. It was done in PHP with MYSQL and I plan to host it on an Amazon EC2 server. My client warned me that he will be email blasting to about 10k customers so my site needs to be able to handle that surge of clicks from those emails. I have two questions:
1) Which Amazon server instance should I choose? Right now I am on a Small instance, I wonder if I should upgrade it to a Large instance for the week of the email blast?
2) What are the configurations that need to be set for a LAMP server. For example, does Amazon server, Apache, PHP, or MySQL have a maximum-connections limit that I should adjust?
Thanks
Technically, putting the static pages, the PHP and the DB on the same instance isn't the best route to take if you want a highly scalable system. That said, if the budget is low and high availablity isn't a problem then you may get away with it in practise.
One option, as you say, is to re-launch the server on a larger instance size for the period you expect heavy traffic. Often this works well enough. You problem is that you don't know the exact model of the traffic that will come. You will get a certain percentage who are at their computers when it arrives and they go straight to the site. The rest will trickle in over time. Having your client send the email whilst the majority of the users are in bed, would help you somewhat, if that's possible, by avoiding the surge.
If we take the case of, say, 2,000 users hitting your site in 10 minutes, I doubt a site that hasn't been optimised would cope, there's very likely to be a silly bottleneck in there. The DB is often the problem, a good sized in-memory cache often helps.
This all said, there are a number of architectural design and features provided by the likes of Amazon and GAE, that enable you, with a correctly designed back-end, to have to worry very little about scalability, it is handled for you on the most part.
If you split the database away from the web server, you would be able to put the web server instances behind an elastic load balancer and have that scale instances by demand. There also exist standard patterns for scaling databases, though there isn't any particular feature to help you with that, apart from database instances.
You might want to try Amazon mechanical turk, which basically lots of people who'll perform often trivial tasks (like navigate to a web page click on this, etc) for a usually very small fee. It's not a bad way to simulate real traffic.
That said, you'd probably have to repeat this several times, so you're better off with a load testing tool. And remember, you can't load testing a time-slicing instance with another time-slicing instance...