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Ok, so I would like to build my application in a way that allows for each organization to get their own instance.
My way of thinking here, is that I could do something with AWS or digital ocean or whatever to deploy my java (dropwizard) application every time a new client registers their company with us.
This would be virtualized, I would be hoping, so I would have those instances running on various virtual servers.
Basically, when a company registers... I would like to spin up an instance of the core API, and an instance of the DB server (or the two could be one instance here, I guess)
Is this a thing? I would google it, but I am not fully sure what to be looking for!
I know this is not a dropwizard question - but I tagged it this way because it is a dropwizard application I am building - and I figure people in that community may have had similar concerns! Please feel free to edit!
You would need to automate the process of spinning up an environment using something like CloudFormation, Ansible, Terraform, Chef, Puppet, etc. There are a lot of tools in this space. These tools are called Infrastructure as Code (IaC). Once you have it automated, setting up a new environment for a new customer would be a simple task of kicking off the appropriate script.
I'm new to the configuration management and deployment tools. I have to implement a Continuous Delivery/Continuous Deployment tool for one of the most interesting projects I've ever put my hands on.
First of all, individually, I'm comfortable with AWS, I know what Ansible is, the logic behind it and its purpose. I do not have same level of understanding of Docker but I got the idea. I went through a lot of Internet resources, but I can't get the the big picture.
What I've been struggling is how they fit together. Using Ansible, I can manage my Infrastructure as Code; building EC2 instances, installing packages... I can even deploy a full application by pulling its code, modify config files and start web server. Docker is, itself, a tool that packages an application and ensures that it can be run wherever you deploy it.
My problems are:
How does Docker (or Ansible and Docker) extend the Continuous Integration process!?
Suppose we have a source code repository, the team members finish working on a feature and they push their work. Jenkins detects this, runs all the acceptance/unit/integration test suites and if they all passed, it declares it as a stable build. How Docker fits here? I mean when the team pushes their work, does Jenkins have to pull the Docker file source coded within the app, build the image of the application, start the container and run all the tests against it or it runs the tests the classic way and if all is good then it builds the Docker image from the Docker file and saves it in a private place?
Should Jenkins tag the final image using x.y.z for example!?
Docker containers configuration :
Suppose we have an image built by Jenkins stored somewhere, how to handle deploying the same image into different environments, and even, different configurations parameters ( Vhosts config, DB hosts, Queues URLs, S3 endpoints, etc...) What is the most flexible way to deal with this issue without breaking Docker principles? Are these configurations backed in the image when it gets build or when the container based on it is started, if so how are they injected?
Ansible and Docker:
Ansible provides a Docker module to manage Docker containers. Assuming I solved the problems mentioned above, when I want to deploy a new version x.t.z of my app, I tell Ansible to pull that image from where it was stored on, start the app container, so how to inject the configuration settings!? Does Ansible have to log in the Docker image, before it's running ( this sounds insane to me ) and use its Jinja2 templates the same way with a classic host!? If not, how is this handled?!
Excuse me if it was a long question or if I misspelled something, but this is my thinking out loud. I'm blocked for the past two weeks and I can't figure out the correct workflow. I want this to be a reference for future readers.
Please, it would very helpful to read your experiences and solutions because this looks like a common workflow.
I would like to answer in parts
How does Docker (or Ansible and Docker) extend the Continuous Integration process!?
Since docker images same everywhere, you use your docker images as if they are production images. Therefore, when somebody committed a code, you build your docker image. You run tests against it. When all tests pass, you tag that image accordingly. Since docker is fast, this is a feasible workflow.
Also docker changes are incremental; therefore, your images will have minimal impact on storage. Also when your tests fail, you may also choose to save that image too. In this way, developer will pull that image and investigate easily why your tests failed. Developer may choose to run tests in their machine too since docker images in jenkins and their machine are not different.
What this brings that all developers will have same environment, same version of all software since you decide which one will be used in docker images. I have come across to bugs that are due to differences between developer machines. For example in the same operating system, unicode settings may affect your code. But in docker images all developers will test against same settings, same version software.
Docker containers configuration :
If you are using a private repository, and you should use one, then configuration changes will not affect hard disk space much. Therefore except security configurations, such as db passwords, you can apply configuration changes to docker images(Baking the Configuration into the Container). Then you can use ansible to apply not-stored configurations to deployed images before/after startup using environment variables or Docker Volumes.
https://dantehranian.wordpress.com/2015/03/25/how-should-i-get-application-configuration-into-my-docker-containers/
Does Ansible have to log in the Docker image, before it's running (
this sounds insane to me ) and use its Jinja2 templates the same way
with a classic host!? If not, how is this handled?!
No, ansible will not log in the Docker image, but ansible with Jinja2 templates can be used to change dockerfile. You can change dockerfile with templates and can inject your configuration to different files. Tag your files accordingly and you have configured images to spin up.
Regarding your question about handling multiple environment configurations using the same Docker image, I have been planning on using a Service Discovery tool like Consul as a centralized config/property management tool. So, when you start your container up, you set an ENV var that tells it what application it is (appID), and what environment config it should use (ex: MyApplication:Dev) and it will pull its config from Consul at startup. I still have to investigate the security around Consul (as if we are storing DB connection credentials in there for example, how do we restrict who can query/update those values). I don't want to just use this for containers, but all apps in general. Another cool capability is to change the config value in Consul and have a hook back into your app to apply the changes immediately (maybe like a REST endpoint on your app to push changes down to and dynamically apply it). Of course your app has to be written to support this!
You might be interested in checking out Martin Fowler's blog articles on immutable infrastructure and on Phoenix servers.
Although not a complete solution, I have suggestions for two of your issues. Although they might not be perfect, these are the practices we are using in our workflow, and prove themselves so far.
Defining different environments - supposing you've written a different Ansible role for each environment you launch, we define an environment variable setting the environment we wish the container to belong to. We then download the suitable configuration file from an S3 bucket using the env variable set before into the container (which should be possible if you supply AWS creds or give your server an IAM role) and inject these parameters into the code when building it.
Ansible doesn't need to log into the docker app, but the solution is a bit tricky. I've tried two ways of tackling this problem, and both aren't ideal. The first one is to download the configuration file as part of the docker image command line, and build the app on container startup. While this solution works - it breaches the Docker philosophy and makes the image highly prone to build errors.
Another solution is pushing several images to your docker hub repo, and then pulling the appropriate image according to the environment at hand.
In a broader stroke, I've tried launching our app completely with Ansible and it was hell, many configuration steps are tricky and get trickier when you try to implement them as a playbook. When I switched to maintaining the severs alone with Ansible, and deploying the app itself with Docker things got a lot easier.
I've got an env.config in source control but pretty much the only things I can put in it are things that relate to all my various environments (production, staging). I've got environment specific settings that I want to add to the env.config file (for instance, the DB host) that will change from environment to environment. How can I handle these differences? Right now I'm doing it from the AWS console where I can manage it in the GUI on a per-environment basis, but I'd love to be able to change a lot of this stuff from git so I don't have to be logging into the console whenever I want to change something.
Is there any way to have multiple, environment specific config files?
So this has been posted before in the AWS forums. (https://forums.aws.amazon.com/thread.jspa?messageID=529373) So far there's only workarounds! The problem is that the .config files would require some logic to figure out what environment you're attempting to target. Personally I don't think any logic is required, as you could simply namespace the config settings based on the AWS environment name you're targeting.
I think your usecase is similar to what is discussed in How to configure Elastic Beanstalk for RDS
You may want to use 'eb branch'. You can then have multiple environments with different configurations.
More documentation on eb branch here
We have our production site in Elastic Beanstalk. SNS notifications is good feature to keep us updated about the environment status whenever it changes. But, we want to watch the production environment logs closely.
Our project is a java webapplication, we want to check the status of the production environment from other beanstalk environments i.e., beta and staging environment which are also in the same region and within the same application.
Our goals are to
use aws sdk or other aws tools to get the production beanstalk tomcat logs and display in our beta site on some page.
Run some tool periodically from the Beta environment on Live environment. Which basically does the testing of the sites, i.e., whether all code level mappings are good, if any exceptions then email them.
if we break down the point2 into further more -
We have quartz scheduler to schedule a job at a particular time. We are planning to add some script which test the complete environment periodically. Are there any Beanstalk built in tools that tests the complete site, accessing all URLS and testing the DB to java serialize object classes mappings (hibernate mappings) etc.,
We do use S3 elastic beanstalk bucket to check tomcat logs, but would like to implement the step1 & step2 if possible.
--
Thanks
For Item #1:
I don't recommend using beta and dev to watch production. Instead, here's what I'd do:
Setup Pingdom on all the three environments, so we could have a close eye on uptime
Review the Logging Code. Do you have a explicitly pattern/idiom for exception handling in place? Are your logging functioning?
Setup Papertrail with Logback. Why? You'll have realtime aggregate log tailing for each and every machine you setup a syslog receiver for. For beanstalk-maven-plugin, we are about to release an archetype (see an example 'blank' project created out of it). Even if you're not using, its worth it so see how to use it.
Setup Log Rollout to S3. As it is, the usage is quite useless. I suggest you work into something to import for analysis (or better yet: Export for usage from Hive - Which is something Papertrail Does)
Define your Health Check Code accordingly. Think about what could go wrong, in terms of dependencies
Look / Set up some CloudWatch metrics. If you application is heavy and you're on a t1.micro, which conditions it would spike? Use that at your advantage
That are just a few ideas.
w/r/t Item #2:
I suggest you rethink your structure. I actually dislike the idea of using crontab in elastic beanstalk servers, since its error prone (leader_only? Managing output?). Instead, I use my newer favourite crontab webapp - Jenkins, and set up an integration testing / smoke testing artifact, with only the relevant bits to remotely test the instance. Selenium might help, but I guess if your Services are critical, you might be more happy relying in rest-assured, for instance.
Hope it helps.
Suppose I create a site in Wordpress, which is running on Elastic Beanstalk. Now, on the running app I will create posts /pages, upload images, etc. That is, some data, videos, files and records in a database will be added to the running application.
3 questions:
If WordPress is running on Elastic Beanstalk with multiple Amazon EC2 instances actually running my WordPress install, then will those files propagate automatically to all running instances? And will this also happen, if a new EC2 instance is fired up - for example, to handle increased load?
From what I see in AWS console, I can deploy different versions of an app-- but as per scenario above, if I deploy a new version, wont I lose all the files uploaded directly into running app (i.e. files and database records)? How do I keep those and at the same time deploy a new version of my app?
The WordPress team keeps issuing upgrades. Can I directly upgrade my running WordPress install, through the web interface? Or do I have to first upgrade my local version of WordPress, and then upload the new version of the app to Beanstalk? If I have to upgrade my local version and then upload, then again I am back to point 1, i.e. changes made by users directly to the older version of running app. How do I preserve those changes?
I've been working on this as well, and have learned a couple of things that are relevant here -- your question about uploads in particular has been on my mind:
(1) The best way to handle uploads, it seems to me, is to either go the NFS/NAS route like you suggest, but one better than that is to use an Amazon S3 plugin for WordPress, so that any uploads automatically copy up to S3 and the URLs in your WordPress media library reflect the FQDN of your bucket and not your specific site. That way you could have one or ten WP nodes in your Beanstalk and media/images are independent of any one of those servers.
(2) You should absolutely be using RDS here. Few things are easier to work with and as stress-free as a Multi-AZ, reserved MySQL RDS instance. Either that or your own EC2 running MySQL that is independent of the Beanstalk, but why run that when RDS is so much easier?
(3) Yes you definitely have to commit changes to your Git repository or local file first (new plugins, changes to themes, WP upgrades) and then upload/install as a revision to the Beanstalk code. Otherwise, all the changes you make via the web interface to one node will never be in the new load for a new node -- in fact you'll have an upgraded database but an older set of code in the Beanstalk application, so it's likely to create errors of some kind or another.
I took an AWS architecture course, and their advice for EC2 and the Beanstalk is to start to think about server instances as very disposable -- so you should try to think about easy ways for your boxes to provision themselves in the bootstrapping process and to take over work for one another without any precious resources on just one box. So losing an instance should never be a big deal. (This is definitely not how we thought in the world of physical servers, where we got everything tweaked 'just so'.)
Good luck!
Well, I'm no expert, but since no one has answered, I'll give it my best shot.
You are absolutely right--kind of. While each EC2 instance does have some local storage, it is destroyed and reset with each new instance. Because of this, Amazon has things like Elastic Block Storage and S3 for persistent files. I don't know how one would configure WP to utilize this, but that will likely be the solution.
I think this problem is solved by my answer to #1. As for the database, all of your EC2 instances should be pulling from the same RDS location. Again, while you could have MySQL running on each EC2 instance, in the interest of persistence, having a separate database makes more sense.
You, again, have most everything right. Local development should always precede live deployment. Upgrading locally then pushing to the live servers will make sure all of your instances remain identical.
Truth-be-told, I am still in the process of learning all of this too, as I said, I'm not an expert. Hopefully someone else will come along and give a more informed answer. However, the key conceptual hurdle here is the idea of elastic scalability--and the salient point of this idea is the separation of elements between what is elastic/scalable/disposable and what is persistent.
Hopefully that helps.
I have deployed a small Wordpress site on EB, S3 and RDS. S3 holds all static data, such as media uploads. This works through a plugin. RDS holds the database. EB holds the latest deployed application. The application is deployed from my dev environment, with a build script. This way, I just have to press one button and I redeploy.
I wrote an article about it here: http://www.cortexcode.com/wordpress-to-aws-code-example/
While it was at first annoying to work with, the speed of AWS is nice and now it's easier than ever. It used to be that I had to upload a bunch of files over FTP, this is way more efficient. :-)
As an addition to all the great answers already:
1) I can highly recommend EFS but also S3 for media files, so they are served from high availability regions in combination with cloudfront. For Wordpress there is one plugin that really speeds up this ( not affiliated to them, just really like the plugin ). There is also an assets plugin, if you'd like to serve JS, CSS files from S3. For the EFS solution, take a look at the AWSlabs docs on git, and specifically this file on how they mount the uploads file.
In general, EBS is really great for Wordpress, but you'll need to think in a different mindset as compared to other hosting solutions ( shared hosting, managed hosting ).
OK I researched a lot on this particular issue, and this is what I learned--
(1) If a wordpress user uploads some files, then his files will be uploaded only to the virtual machine that is actually serving his request at that time. Eg if currently the wordpress site is cloud-deployed and is using 5 virtual machines, now when user makes request he is directed to one virtual machine-- the one with the lowest load at that point... His uploads are stored only on that server. Current Platform-as-a-service solutions (like Amazon Elastic Beanstalk and App Fog) do not have the ability to propagate the changes to all the running instances. Either that (propagate changes to all servers) or use a common storage by all running instances-- these are the only 2 solutions to this problem. (Eg of common storage would be all 5 running virtual machines using Network-Attached-Storage (NAS)... )
(2) With ref to platforms available currently like Amazon Elastic Beanstalk and App Fog, for example, even if user made changes directly to running app- these platforms rely on the local version of code (which the admin deployed initially to cloud)- and there is no way to update the local version of code (on admin's PC) with the changes made by a user to running app-- hence these changes viz, files are lost-- Similarly, changes in database by user to running app are also lost-- unless the admin is using exactly the same database for his local app (that he deployed to cloud)
(3) Any changes to running apps first have to be made to the local app on admin's PC and then pushed to cloud.
I am working on a Cloud PaaS that addresses all these concerns-- viz updates can be made to running apps, code changes made to running app are also updated in code repository accessible by user...The Proof of concept is ready, hopefully it will be as good as I hope it should be :) -- currently the only thing that is actually there is the website (anyacloudpanel.com) -- design work is going on :)
If there is some rule that I should not mention my website( Anya Cloud Panel) -- then I am sorry -- pls feel free to edit and remove my website URL from my answer :)
Thanks,
Arvind.
Deploying WordPress to AWS Elastic Beanstalk does require some change to the normal WordPress deployment as mentioned here a few times. To answer your questions, here is a great tutorial explaining stateless applications and how to deploy to Elastic Beanstalk:
Deploying WordPress to Amazon Web Services AWS EC2 and RDS via ElasticBeanstalk
Be careful if you use a theme from themeforest for example. Some of them are incompatible with wordpress S3 plugin. Then you're screwed, you can not deploy your wordpress on the cloud.