I use Glassfish Java, and JSP over MySQL for my web applications. Many online people uses this web application and that web-site should not be down.
When I want to deploy a new war file, I should undeploy and deploy the new one for my application at server.
My question is that;
Is there any technology that doesn't need to undeploy my application and just change the appropriate classes so no need to redoploy it again?
There are java technologies that would allow you to replace classes on the fly (like JRebel). But since you're using Glassfish already, you should just start using clustering which is built into glassfish. You'll need either 2.1 or 3.1, as 3.0 does not support clustering. With a Glassfish cluster, you have a load balancer (Apache, Sun Web Server, hardware (Big IP, Coyote), etc) distribute the load among your cluster nodes. When you want to upgrade the app, you can technically do it one node at a time. Setting up the cluster is not the easiest thing in the world, but it is doable and it would get you some great benefits. You'll be able to scale the load by adding new hardware and even using Amazon (or whoever) cloud services. You'll be able to keep your site running even if the hardware fails on one of the nodes.
Personally I'm in the middle of converting from Glassfish 2.1 to 3.1. So far I like the management of the Glassfish 3.1 cluster much better, but I can't personally vouch for how it will run in production, though I have high expectations.
http://download.oracle.com/docs/cd/E18930_01/html/821-2432/gktqx.html#gktob
Jim is right, the best solution is currently to use a cluster and perform a manual rolling-upgrade.
But there is actually work ongoing to address your needs. We are working on a rolling-upgrade feature in a single standalone instance. To sum up in a nutshell (as the specifications have not been published yet), it will let you switch from an application version to another (see application versioning and the enable command) with no downtime. Stay tuned.
Related
I am developing a number of microservices which will run on Open Liberty. I have set up a test server in my eclipse environment which is configured to use all the features required by all the services which I am currently working on.
Whilst this works, it seems a heavy-handed approach and it would be good to test each service in an environment which closely resembles the target server. The services can differ in the set of features they require as well as the JVM settings necessary.
Each service will run in its own docker container and the docker configuration is defined in each project.
Is there a way to better test these services without explicitly setting up a new server for each individual service?
I am not aware of any way to segment the Liberty runtime (its features) nor the jvm (for different jvm settings) for different applications running in a single Liberty instance.
You can set app specific variables and retrieve them using MP Config, but that's not the same as jvm settings and certainly not the same as trying to segment specific features of the runtime to a specific application.
However, in general when testing, I would highly recommend trying to mimic your production environment as much as possible. Since you're planning on deploying into docker, I would do the same locally when testing, and given Liberty's lightweight, composable nature, it's unlikely that you'll hit resource issues locally when doing this (you should only enable the features on each Liberty instance that your app is using to minimize the size of that instance). This approach is one of the big benefits/value provided by containers and Liberty.
In other words, even if you could have one Liberty instance segmented per application, I would not recommend it for your testing because, as you said, "it would be good to test each service in an environment which closely resembles the target server"
I am new to Jboss, want to know if micro services architecture is a right choice on JBOSS. I cannot change the application server as it is decided by client architect and I have no choice.
Want to know whether we can develop micro services with underlying JBOSS application server.
I understand Spring boot comes with embedded tomcat container, which makes it flexible to stop and start, deploy individual service with no impact to other services.
However will that architecture works with JBoss too.
Please suggest.
Thanks,
I actually developed a feasibility study to investigate the solution you mentioned. My conclusion is that it is totally viable to use Micro Service principles in a JBoss Platform.
I used the combination of JBoss \ Spring Boot \ Netflix to create successful Micro Service stack, I personally do that to find a solution to the transaction problem (multiple micro services collaborating) and the fan out problem which caused because excessive Network communication and Serialization costs.
I also wrote a blog about the subject, you might find more details there if you like to, here is the link.
Micro Services – Fan Out, Transaction Problems and Solutions with Spring Boot/JBoss and Netflix Eureka
By the definition what micro services are, then conceptually yes. A micro service is a service that is an independent unit, it could deployed, updated, and undeployed independently without affecting any unrelated part of your application. So that would mean having multiple instances of JBoss for MS and your application calling them through some sort of gateway or any other mechanism depending on your use case. If you plan to deploy all your MS in the same JBoss instance then it defeats the very purpose of a MS. Given that, JBoss wouldn't be a right choice for MS deployment because it will only make your MS deployment infrastructure quite heavy.
Depending on what your client's requirements are, your could possibly keep your webapp in JBoss and deploy your MS containers separately.
It depends on what you want to get out of microservices.
Some of the developers at my organisation looked at Spring Boot but concluded that it's best off being run as a standalone container rather than in JBoss, otherwise you've effectively got two container frameworks competing (SB and JBoss) and a range of associated issues.
Deploying microservices in JBoss won't give you the same flexibility as a true container system like Docker. With Docker you create standalone packages for your microservices that contain all the code, system tools, runtime environment, etc. It can be as small or large as it needs to be. JBoss on the other hand is a large container running a single JVM designed to hold multiple applications. The level of isolation is not the same, and it's not efficient to have JBoss as a container for a single microservice so you have to appropriately size and then deploy to the instance to make use of the resources it has available.
If you're looking at microservices as a way to gain greater control over service lifecycle management (deployment, versioning, deprecating, etc.) as opposed to an automated, web-scale component deployment model a la Netflix or LinkedIn, you could do this adequately with JBoss.
I'm actually looking to do something along these lines here. It won't be true microservices but by packaging and deploying individual, properly versioned APIs rather than monolithic applications and following most of the other principles of microservice development (componentisation, business function focus, stateless etc.) we will be hopefully better able to manage and benefit from our APIs.
Our APIs will all be behind an API gateway and load balancer so we can choose how we distribute the microserves distributed across the JBoss instances and balance resource usage as required. Note that our organisation is relatively small and has relatively low and predictable traffic so this approach should work fine. Your needs however may be different.
I'm building a web app with Backbone.js (I'm not tied to Backbone yet though). I need a back-end framework only for persistence to a database via a RESTful API. However, I also need to able to deploy it as a 'desktop' app for off-line use, i.e. running a local server and launching a browser window, but I don't want users to have to start a server from the command line to run the application.
I can use SQLite as a database since it's only a single user application, it's just the framework that I'm stuck on. I have looked at the following:
Rails and Django: Default web servers are too flimsy, requires Ruby/Python and runs from the command line. I'm aware of the Bitnami stacks but at 99mb it's too big of a dependency and not exactly hidden from the user.
Sproutcore: Run from command line, also too bulky.
Pyjamas Desktop - Depends on MSHTML which I suspect limits my ability to use HTML5 features.
I'm leaning towards creating a Java app that starts a Scala/Lift server instance and opens a web browser, then sits in the system tray (kind of like WAMP). Is anyone familiar with a tool or framework built for user-friendly deployment as a standalone desktop app?
I do not know if PHP is an option for you? Then I would recommend phpdock.
web2py has a standalone deploy-to-desktop feature with no dependency on Python: http://web2py.com/books/default/chapter/29/14#How-to-distribute-your-applications-as-binaries
As Eydun said, phpdock is an option but it's commercially licensed .
I settled on using Java/Spring/H2/Hibernate/Jetty. I find that Jetty serves requests VERY quickly so the application looks real-time when launched in a browser. There is a tutorial on embedding the Jetty server here. I imagine it's quite trivial to build a GUI that launches the server and a browser.
Another Java option is to use the Play Framework, which may be more at home to those coming from a Django/Rails background. However, the documentation for "creating a standalone version of your application" for Play 2.0+ indicates that they have ditched using Java EE containers (Tomcat/Jetty) and WAR files in favor of running the JARs with the bundled copy of JBoss Netty, so it may take a bit of work to get it running the way you want it.
I would recommend the Play Framework approach if you're OK with using/learning Scala.
I love Heroku but I would prefer to develop in Scala rather than Ruby on Rails.
Does anyone know of any services like Heroku that work with Scala?
UPDATE: Heroku now officially supports Scala - see answers below for links
As of October 3rd 2011, Heroku officially supports Scala, Akka and sbt.
http://blog.heroku.com/archives/2011/10/3/scala/
Update
Heroku has just announced support for Java.
Update 2
Heroku has just announced support for Scala
Also
Check out Amazon Elastic Beanstalk.
To deploy Java applications using
Elastic Beanstalk, you simply:
Create your application as you
normally would using any editor or IDE
(e.g. Eclipse).
Package your
deployable code into a standard Java
Web Application Archive (WAR file).
Upload your WAR file to Elastic
Beanstalk using the AWS Management
Console, the AWS Toolkit for Eclipse,
the web service APIs, or the Command
Line Tools.
Deploy your application.
Behind the scenes, Elastic Beanstalk
handles the provisioning of a load
balancer and the deployment of your
WAR file to one or more EC2 instances
running the Apache Tomcat application
server.
Within a few minutes you will
be able to access your application at
a customized URL (e.g.
http://myapp.elasticbeanstalk.com/).
Once an application is running,
Elastic Beanstalk provides several
management features such as:
Easily deploy new application versions
to running environments (or rollback
to a previous version).
Access
built-in CloudWatch monitoring metrics
such as average CPU utilization,
request count, and average latency.
Receive e-mail notifications through
Amazon Simple Notification Service
when application health changes or
application servers are added or
removed.
Access Tomcat server log
files without needing to login to the
application servers.
Quickly restart
the application servers on all EC2
instances with a single command.
Another strong contender is Cloud Foundry. One of the nice features of Cloud Foundry is the ability to have a local version of "the cloud" running on your laptop so you can deploy and test offline.
I started working on the exact same thing as what you said a few weeks ago. I use Lift, which is a great framework and has a lot of potential, on top of Linux chroot environment.
I'm done with a demo version, but Linux chroot is not that stable (nor secure), so I'm now switching to FreeBSD jail on Amazon EC2, and hopefully it'll be done soon.
http://lifthub.net/
There are also other Java hosting environment including VMForce mentioned above.
If you are looking for a custom setup which also has the ease of deployment that heroku offers: http://dotcloud.com. They are invite only right now but I was given access in under three days. I am working on a Lift/MongoDB project there and it works well.
Off the top of my head, only VMForce comes to mind, but its not available yet. This will be a Java-oriented service, so that probably means you'll have to spend a wee bit of time figuring out how to package the app.
For more discussion, there was a debate about this in 2008.
I'm not entirely sure if it's really suitable or not, but people have deployed Scala applications to Google App Engine, for example http://mawson.wordpress.com/2009/04/10/first-steps-with-scala-on-google-app-engine/
Actually you can run scala on heroku right now. You don't believe it?
https://github.com/lstoll/heroku-playframework-scala
I'm not sure the tricks lstoll has used are legit but using the
new cedar platform where you can run custom processes and some
ingenious Gemfile hacking he has managed to bootstrap the Java
play platform into a process. Seems to work as he has a live
site running a test page.
Stax cloud service offers preconfigured lift project skeleton. Also, there is a tutorial on how to deploy lift project to appengine.
For a variety of unfortunate management reasons (budget constraints etc.) I, the developer, have been put in the position to deploy the app in a production environment. The catch is that I don't have any experience in production EJB application server deployment. That said, they are aware that there are no guarantees of success.
The context:
The dev server runs on the latest version of Netbeans with Glassfish v3, on a mac machine
98% / 99% uptime is ok, there are no financial/critical transactions
It is a client/server EJB 3 app, and the web tier, business tier, and resource tiers currently run on the same machine.
I have the liberty to choose the hw/sw infrastructure
Load estimations: 10 simultaneous connexions avg, rare 200 peaks
The outbound public data is text/small pics (it's for iPhone clients), inbound HTTP text only
Basic maintenance will be taken care of (backup, server reboot, etc)
My questions for production deployment:
What are the must haves infrastructure-wise? Minimum system specs etc?
Is it ok to keep Glassfish v3?
Which configuration aspects of the server should I focus on?
Worst case scenario: if I deploy the same software infrastructure (Netbeans/Glassfish v3) as during the development, would the server keep up?
Any piece of advice would be most welcome. Thanks!
For the architecture, you can start small with just a single GlassFish instance with no front web server (GlassFish has one built in that is very capable). If you can wait for the release of GlassFish 3.1 you'll be able to add instances (clustered or standalone) and offer scalability and centralized admin.
Most production instances of GlassFish I've seen run with 1GB-2GB of JVM heap (-Xmx) but your mileage may vary if you load lots of data in memory or if you use some frameworks. If you want better reliability, having them on separate machines is a plus obviously. With two instances on the same machine you can offer continuity of service if one instance fails (but not if the machine fails).
I'd suggest scripting as much as possible the provisioning of the resources (connection pool , JDBC datasource, etc...) and applications using the "asadmin" command-line tool and try to not use NetBeans on the production platform.
Benchmarking with simulated load sounds like a wise thing to try to put together before going live and this survival guide will probably come in handy.
You don't mention the database. Isn't there one?
I suggest the following:
Not a Mac expert but I'll say go with 6GB or more RAM
HDD space is not a problem these days
Do not know much abt Mac Processors (watever eq of dual core etc)
Personally I have not used GF3 in Production but I hope it's stable now so you should be ok.
System Architecture:
Receive all HTTP requests on some web server (Apache or Sun web server) and load balance with your Glassfish server(s).
Now depending on your physical (or virtual) machines create instance of Glassfish Application Server on each machine. If you just have one machine then create atleast 2 instances of Glassfish. This will help to put one node down for maintaince and other to keep going.
As far as deployment is concern make sure you stop debug logs and fine tune JPA logs etc.
Use Ant or other scripts to deploy code and taking backup of existing code.
I hope this will help to kick start and rest you can ask or solve as you go along.
Good luck.