Constructing Red Hat Enterprise Linux 4

A large class of new Linux deployments consists of proprietary UNIX migrations. These users represent a set of enterprise customers who have high expectations (a euphemism for highly demanding). Traditional functionality gaps in Linux consist of robust software volume management capabilities. In response to these needs, over the course of Red Hat Enterprise Linux v.4, Red Hat acquired a strong team of storage-centric experts when Red Hat purchased Sistina. In this manner, Red Hat now employs the major upstream developers of the Logical Volume Manager (LVM) technology.

Overall ease of use has been improved in the installer, where it now enables the user to create LVM volumes. Through the use of a graphical interface in Disk Druid, usage of LVM is much more approachable to the end user. Another example of ease-of-use improvements are the capabilities to grow both LVM volumes and ext3 filesystems that are on-line. This obviates the need to unmount the filesystem, back up, grow the volume, reformat the filesystem and restore the data.

We also wanted to take open-source storage management to the next level to provide a cluster filesystem. The industry trends have been toward distributed computing among large sets of commodity computers. Although that yields cost savings in hardware, it increases costs of managing storage and filesystems among a distributed pool of servers. To address this need, Red Hat has augmented the LVM layer to operate in a clustered environment by layering a robust cluster filesystem called GFS.

In keeping with Red Hat's core values of being an open-source player, the complete source code base for LVM and GFS is now freely available to the Linux community at large. Ongoing development has rekindled industry-wide contributions. Cluster Suite is the name of the productised version of GFS and LVM, which is layered on top of Red Hat Enterprise Linux.

One of Red Hat's largest areas of increased investment is in what we refer to as the desktop space. Under the guidance of Havoc Pennington, we have formed an extensive close-knit team of developers. The primary mantra of the desktop team has been ease of use. If you look closely at the new adoptions of Linux you will see an increasing trend of usage in less computer-savvy scenarios. Examples include kiosks, call centers, government agencies and earlier grade-school levels.

The desktop team worked with our application developers to identify the most useful application set. Although there are more than 80,000 projects on Sourceforge.net, for example, it is impractical to include all of them in our distribution. One of our main roles as a system integrator is selecting and organizing the most useful applications. In v.4 we have reorganized how the applications are listed in the menus so as to be grouped logically by function.

Inside the walls of Red Hat, we take the open-source model to an extreme, where product decisions are debated by anyone who has a nearby soapbox. Given that everyone is a self-proclaimed authority on “what the users want” and what “usability” means, this provided ample fodder for highly emotionally charged debates. This all came to a head in the selection of the default browser. The main contenders were Firefox and Epiphany. The on-line e-mail debates raged on. In the end, Havoc pulled all interested parties together for a raucous conference call to hash things out. The result was the selection of Firefox. Given the huge amount of attention that Firefox has been garnering, both in the media and practical deployments, we think we made the right choice.

These debates are a core part of being at Red Hat. They become so volatile because the crew sincerely cares about what they are doing. Most people here feel part of something bigger than a small company. This high level of energy, creativity and enthusiasm found at Red Hat makes it extremely challenging to be a manager. Sometimes it seems like I'm a referee to a crew of prize fighters, who in addition to sparing with each other, often share a punch to the head with me too. Perhaps I should have strived to find a more constructive example. It's really not combative here, just highly stimulating and challenging. After living in this world for 3.5 years now, I can't imagine what its like to work at a place that would be “just a job”.

One of the key usability technologies that our developers (including Havoc Pennington and John Palmieri) were involved with is D-BUS (see Resources). D-BUS is a communication and event mechanism that enables a range of desktop applications to compliment each other in a coordinated manner. For example, the insertion of a CD results in launching of a corresponding application depending on media format type. Similarly, D-BUS is used for USB device hot plug, for example, to initiate configuration and startup of network services or mounting filesystems from USB pendrives.

Ease of use was further enhanced through the bundled collection of third-party proprietary applications. This is done for the convenience of the end user, so that it doesn't become an egg hunt for them to find commonly used applications. This resulted in the bundling of RealPlayer, Helix Player, Adobe Acrobat Reader, Citrix, Macromedia Flash and a Java runtime environment (JRE).