rPath's rBuilder 5 Streamlines Linux Virtual Machine Management

By Jason Brooks  |  Posted 2009-07-23

rPath's rBuilder 5 Streamlines Linux Virtual Machine Management

With its rBuilder 5.2.1, rPath aims to streamline the deployment and maintenance of application workloads by providing IT organizations with the tools to roll their applications into Linux-based software appliances that are ready to deploy on popular server virtualization platforms, cloud computing services or bare-metal systems.

Rather than manage the operating system, application and virtual container layers in separate processes, rBuilder enables organizations to fold these operations into a single system that pairs applications with "just enough" operating system components to meet their needs; that packages the application-plus-OS bundles into the formats required by various hosting platforms; and that keeps these appliances up-to-date with security and bug fix patches.

Check out eWEEK Labs' gallery of rBuilder 5.2.1 here. 

rBuilder Version 5.0, which was released in April, introduced several major new features, including additional Linux distribution options; a new, Flash-based interface; and a new management console through which administrators can directly manipulate appliances on various virtualization environments.

In my tests of rBuilder, which began with a pre-5.0 release of the product and ran through the current 5.2.1 version, I was impressed by the ease with which I could churn out virtual machine images for immediate deployment on the Amazon EC2 and VMware ESX environments that I tapped for testing. I also appreciated the handy Web-based management interface that rBuilder pairs with the appliances it creates.

However, I found the process of getting my chosen applications configured properly much more complicated than the product's point-and-click graphical interface might suggest.

For my tests, I worked primarily with the Mediawiki application that powers Wikipedia--an application that I know can be implemented very well with rPath's tools because the company offers a freely available Mediawiki appliance for download from its site. The rPath-built Mediawiki appliance boasts an initial setup process that's folded into the appliance's Web management interface, and a slick backup option that covers both uploaded files and the Mediawiki database.

Building a Mediawiki appliance on my own was a much less streamlined affair. For example, while rBuilder managed to detect automatically and provide most of the OS dependencies that my test applications required, the product didn't catch everything on its own, and I couldn't tell if rBuilder had missed any required components without building and launching my appliances first. To get everything configured properly, I ended up having to cycle through the define, build and launch process many times, and spend time learning about rPath's conary recipe language to tweak my package definitions.

With that said, rBuilder is well worth evaluating, and rPath makes evaluations fairly easy to conduct. rBuilder is available in hosted and on-premises versions, and both flavors are freely accessible.

The on-premises version of rBuilder is free for use with up to 20 running virtual instances. The hosted version of rBuilder, called rBuilder Online, is completely free, but all appliances built and stored on rBuilder Online are publicly accessible.

Multiple Linux Platforms


rPath maintains its own Linux distribution, rPath Linux, from which rBuilder can pluck the components required to build software appliances. rPath Linux is a fairly conservative distribution that's capable of serving most Linux applications without issue.

However, for applications designed or certified to work on a specific distribution, using rPath's own Linux can pose support hurdles. It's in these cases that rBuilder's support for Linux distributions beyond rPath Linux comes in handy. rBuilder offers the choice of SUSE Linux Enterprise Server 10 or 11, Ubuntu Hardy or the Red Hat Enterprise Linux 5 clone, CentOS 5. For the SLES options, you must configure rBuilder with an activation key confirming that you're entitled to run the distribution.

When I embarked on my appliance-creation journey, rBuilder prompted me to choose one of these distributions. Later, I could easily switch platforms through the product's Flash-based interface. I switched appliances from rPath Linux 2 to CentOS and vice versa.

Virtualization Target Support

Also new in the 5.x versions of rBuilder is a management console through which I could configure virtualization host targets to link up with rBuilder. I could choose from on-premises VMware ESX Server or Citrix XenServer hosts, or the cloud-based Amazon EC2 or the Globus Workspaces Cloud. I tested with a VMware vSphere installation and with an Amazon EC2 account. In both cases, I could see a list of the running instances on the services, as well as launch or terminate new instances from rBuilder.

I could also create virtual images in a fairly comprehensive range of other formats, including those for Microsoft Hyper-V, Virtual Iron, Parallels, QEMU, installable DVD or CD ISOs and plain TAR archives.

Flash-based Interface

Among the most striking changes between the 4.x and 5.x versions of rBuilder is a move from an HTML and Javascript-based Web interface to a new Web front end built on Adobe's Flash framework. The Flash interface gives rBuilder a look and feel more akin to a regular desktop application, while retaining the cross-platform support of the HTML interface.

Overall, my experience with the new interface was positive. In my first experiences with the new UI, just after Version 5 became available, I was tempted to say that rPath had pushed the envelope a bit too far in terms of what's feasible with a Flash-based application, but the company has managed to iron out most of the early wrinkles I encountered.

For example, while testing earlier 5.x builds of rBuilder, I experienced some performance issues with the Flash-based interface, which tended to result in my browser--and all its open tabs--locking up for short periods of time. Specifically, I experienced these problems while connecting to VMware ESX server targets. With Version 5.2.1 of rBuilder, those particular lockup issues seemed to have been ironed out.

However, there were some Flash issues even in Version 5.2.1. In one case, I triggered a build of one of my appliance images, but the operation wasn't reflected in the interface. I clicked a couple more times to launch the build, but it wasn't until I refreshed the page that I could see that each of my clicks had indeed added a new build process to the product's queue. The interface offered no option to cancel the redundant operations, so I had to either wait for them to finish or visit a separate rBuilder administration console to cancel them.

Executive Editor Jason Brooks can be reached at jbrooks@eweek.com.

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