FAQ

Frequently Asked Questions on Cloud42

If you think a question is not answered here, please feel free to contact us.

What do I need to run Cloud42?

Coud42 is a Web application written in Java.

In order to run it, you need a installed Java SE 1.6 environment (1.5 should do it, too) and a Servlet-Container like Apache Tomcat or Jetty. Cloud42 probably will work with other containers, too, but it was tested using Tomcat and Jetty, so we recommend the usage of one of them.

Both of these containers serve as web servers, too, so you do not need any more infrastructure. Furthermore, both containers are available for Windows as well as for Linux and several other operating systems.

Hint: setting up Tomcat on an EC2 AMI instance might be a good idea. This way, you can run Cloud42 "in the cloud".

Does Cloud42 need a database?

Yes, a database is needed for storing user accounts and credentials for the GUI part of Cloud42. The Web service layer requires a database in order to persist subscribers for the notification mechanism.

However, you do not need to setup a special database server. Cloud42 is distributed with HSQLDB database, a small and lightweight database system. So you do not need to make any configuration. At startup, Cloud42 will create all necessary tables and views for you.

Can I use the GUI and the Web service interface separately from each other?

Yes, the two parts of Cloud42 are fully separated Web applications (WAR files), so you can deploy only one of them or both at the same time.

I want to develop my own application based on the Cloud42 Web service interface. Where can I get help and assistance?

First of all, visit the documentation section where you can find sample SOAP requests and a full JavaDoc for the Web service methods and all other interal classes as well as other useful stuff.

If you are interested in individual help and support via email and if you want to retrieve exclusive updates and hot-fixes, you can purchase a commercial licence. Contact us if you want to know more.

Cloud42 does not support all the brand-new features offered by EC2 or AWS in general. Why?

Cloud42 is a third-party software maintained by just works! Software, a very small software company. We do not collaborate with AWS directly at the moment. Instead, Amazon with its huge team of developers updates or enhances its services very often and it is difficult to follow all their updates and to implement each feature right when it is added.

Therefore, your help is appreciated: if you want to add a feature that you are missing, feel free to do so and please contribute your enhancements. Just contact us in any case.

I want to contribute or support Cloud42. How can I do this?

There are many ways you can support Cloud42. Have a look at this page.

I want to get a deeper understanding of Cloud42. What can I do? Where can I find material?

In case you want to familiarize yourself with the architecture of Cloud42 or you want to get introduced into the used technologies, it is recommended that you read the diploma thesis Cloud42 is based on. Especially the chapters 3 and 4 may contain a lot of interesting things for you.

Where does the name "Cloud42" come from?

Well, Cloud42 is a management framework for Cloud Computing, so the part "Cloud" was an obvious choice. The "42" is intented to be an allusion to 42 as simple answer on all questions in the famous book The Hitchhiker's Guide to the Galaxy from Douglas Adams. This number was chosen to point out that Cloud42 can be used for any purpose you can think of, thanks to the presence of both a GUI and a Web service interface.

I installed Cloud42 web application or Web service, but it does not list my images and/or instances!

Make sure you selected the correct region (the region your instance was launched in) in the web application (dropdown box on the upper right of the screen). When using the Web service interface, it is necessary to pass the parameter regionUrl with each request. See the docs of the Web service interface for more information.

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