Key Findings
It's time to put both feet in the water - Linux is a credible alternative now for the core of the data centre, and for the client within two years.
Freedom of choice - The most important attribute of Linux is the independence afforded from the hardware platform.
Linux is a cost effective UNIX replacement, and worthy competitor to Microsoft Windows Server in many areas.
Linux on the client is gaining credence, with offerings available from Red Hat, IBM, Novell, and Sun.
Ignore generalised Total Cost of Ownership (TCO) evaluations, the TCO of Linux varies dependent on an individual organisation's circumstances.
The Linux ecosystem is developing quickly and is a major driver of the adoption of Linux, especially for the main enterprise distributions from Red Hat and Novell.
The public sector is showing leadership in this area, and beginning to embrace Linux and Open Source in a major way.
Open Source software tends not to be innovative, but does produce efficient, secure, and robust code.
For many, already using Windows, it remains the best strategic choice, as does proprietary UNIX at the very high end.
Introduction
IT management needs to take a long hard look at their heterogeneous systems infrastructure, and to put in place steps to reduce the escalating costs that are in part driven by the number of incumbent Operating Systems (OSs) in the environment. Very few IT managers ever go out to purchase an OS, but it is the provision or development of services to meet the business objectives and requirements that is the main driver. Above all else, what Linux provides is the opportunity to reduce the number of platforms supported, by removing the need for close coupling between the OS and specific hardware.

It seems to many in the IT industry and outside that Linux has come from nowhere to capture a significant share of the enterprise server market. The actual figures are hotly disputed among those in the vendor community, especially as the engagement model for Linux makes accurate numbers difficult to determine. However, what must be acknowledged is that Linux is definitely gaining traction in the enterprise, especially against UNIX derivatives. In little more than 15 years Linux has advanced from the garage into the core of the enterprise, has achieved credibility in the server environment, and is now even beginning to threaten Microsoft's iron grip on the client OS market. The Linux generation has begun and make no mistake the era of Open Source development, with Linux as a leading exponent, is a reality.

Let's be clear though, Linux, while offering an end to hardware vendor lock in, more control, and good resilience, is no universal remedy, there are the same issues as with the deployment and maintenance of other platforms, and Microsoft Windows continues to be an effective alternative. In the short-term adding Linux to the mix can increase skill requirements and complexity, making it imperative that management processes and administration tools are in place to allow the centralised control of the IT environment. But an organisation that commits itself to just two OSs, i.e. Windows and Linux, will over time reduce the skill sets required for management and administration.
Business Issues
Everybody now accepts that Linux in the enterprise environment is not free. However, TCO is complex with many variables to consider, making direct comparison difficult as each organisation is different. Little attention should be paid to the generalised TCO studies generated by many in the industry around whether UNIX, Windows, or Linux is the most expensive to operate. IT management must retain its objectivity selecting the most appropriate and cost effective OS for the selected services and applications. In the end, as with any IT deployment, it hinges on what the specific business and technical requirements are. What is significant is that Linux is now a valid option for enterprise use.

The on-going SCO litigation saga with regard to provenance of Linux code, involving many leading IT industry vendors, and some customers, looks set to continue for some time to come. This backdrop can be unsettling for those deciding whether to make Linux a strategic OS. However, this is not seen as a major threat and should not cloud the decision-making process, especially as many vendors will indemnify users against any unfavourable judgements.

The patent protection regulation changes proposed by the EU have the potential to cause further difficulties for the Open Source community, of which Linux is a part. If the proposal is accepted in its current form it will allow patents to cover code, data structures, and process descriptions. The danger is that Open Source projects will find patent licensing costs prohibitive stifling code reuse and innovation, as well as commercial software vendors possibly using the regulations to close down Open Source projects. This should not detract from the fact that Linux has evolved into a dependable, enterprise-ready environment capable of meeting business and technical requirements.

The absence of accountability for Linux can be a worry for many organisations, with liability, and the provision of a warranty difficult to pin down to a developer. There is also a concern as to the future direction the OS might take, as there is no guarantee that new kernel developments will cater for business needs. The establishment of enterprise-focused distributions and the availability of support from the Linux ecosystem, including the control and testing provided by the Open Source Development Lab (OSDL), should significantly diminish these concerns.

Technology Issues
Linux is very much a disruptive technology where migration should not be taken too lightly, especially the retraining needs and organisational changes required when moving from Windows to Linux. Another possible barrier to adoption is the total cost of acquisition, which should be given careful consideration, with the softer issues such as the cultural aspects and management support afforded particular attention.

A number of significant technology trends within the IT industry have made Linux a leading contender for inclusion in an organisation's infrastructure. Intel-based architecture dominates the enterprise IT environment. With Moore's law continually advancing performance and the increasing use of blade technology, x86 hardware is a feasible option for all data processing requirements, even for large database and transactional applications. Linux's ability to run on this industry standard hardware makes it a prime contender to replace proprietary UNIX solutions.

This hardware independence is especially important as organisations start to move into the 64-bit world. It is by no means certain which processor will become the industry standard from Intel Xeon and Itanium, AMD Opteron, and IBM POWER. Being hardware agnostic gives the flexibility to utilise whichever system provides the best performance and value now and in the future. This portability at last presents the IT manager with the leverage to maximise the best price from hardware vendors.

There is a continuing focus on doing more with less, consolidating servers to maximise utilisation along with a move to utility computing. Linux allows the number of OSs deployed in an organisation's infrastructure to be decreased, thus reducing the administration overhead of the IT environment. In addition, the connectivity features built into Linux allow integration with Microsoft, Novell, and other networks, which can help with the implementation of a consolidation strategy.

The latest 2.6 Linux kernel release, made available at the end of 2003, builds on the previous version with enhancements that include support for NUMA servers, hyperthreading, scalability improvements, security-related changes, and more legacy support. Novell plans to include the new kernel in its SUSE LINUX enterprise distribution about the time that this report is published and Red Hat by early 2005.

Linux is, of course, not the only alternative going forward. Microsoft Windows, while not being completely hardware agnostic does run on industry standard x86-based hardware. The combination of Microsoft Windows XP and Microsoft Windows Server 2003 offers an IT platform which is compelling for the enterprise user, especially with the focus on improved security, reliability, availability, and scalability. Where Windows has a significant advantage is in the totality of software stack, developer tools, available functionality, and integration, especially in the desktop environment. A shortcoming is perceived as the on-going licensing costs, an issue that ironically Microsoft itself brought to the fore.

There could now be the beginnings of a sea change on the desktop, with Linux client offerings available from Red Hat, IBM, Novell, and Sun. However, gaining credence will be no easy task, and all the solutions must deliver the equivalent convenience and integration of the incumbent Windows environment. A number of early adopter public sector organisations such as Munich, City of Bergen, and Schwabisch Hall councils are now deploying Linux and Open Source on the desktop. For the sceptical, download Knoppix 3.4 or SUSE Live 9.1 and boot from the CD to see how far the Linux desktop has come in recent times. The Open Source office tools, deployed on a Linux desktop will, however, be playing ‘catch-up' with Microsoft Office for the foreseeable future. The only product that appears to have ‘leapfrogged' the Microsoft stable to date is the Mozilla Browser.

Market Issues
An important reason why Linux has successfully evolved into an enterprise ready OS is the creation of a mutually beneficial ecosystem. Over the last couple of years the Open Source community and the commercial sector have adapted to each other and this has allowed the commercialisation of Linux to grow from strength to strength. The use of the Open Source software development model has proved very good at producing efficient and robust code, but possibly not the catalyst for innovative improvements that has been advocated by many in the Open Source community. The openness and flexibility surrounding Linux is particularly appealing to public sector organisations.

To be a credible offering in the enterprise space Linux must have Independent Software Vendors' (ISVs) support. While in the early days this was lacking this is no longer the case, especially as IBM has provided active assistance to ISVs to port their offerings. Linux is now a tier 1 OS for the majority of ISVs and hardware vendors. The main benefactors have been the Linux enterprise distributions from Red Hat and Novell, making them the leaders in the market. The availability of reference architectures from HP, Oracle, and others has further aided confidence in the Linux market.

The health of the Linux ecosystem very much depends on service providers to supply Linux support and other resources to users. IBM has played a leading role in growing the Linux market. Additionally, many ISVs, hardware vendors, and service providers donate software back to the Open Source community for inclusion in the Linux kernel. A worry is the fragmentation of Linux, however, the fact that no single vendor controls the kernel has so far prevented this.

There are significant trigger points on the horizon for many IT managers including the withdrawal of Windows NT support, hardware replacement, and the Windows Longhorn release. Linux offers an alternative and is worthy of consideration as and when decisions on future OS strategy become necessary. Section Two - Introduction
Following the Management Summary, the Introduction sets the scene, giving an overview of the considerations, concepts, and business benefits of Linux in the Enterprise.

Section Three - Technology Features
This section describes the main features, standards, and technologies appropriate when using Linux in the Enterprise.

Section Four - Architectures and Models
This part of the Report takes a closer look at the architectures pertinent to the adoption of Linux in the Enterprise.

Section Five - Deployment
This section uncovers the issues and advantages of Linux in the Enterprise, along with why the OS is relevant to the public sector and SMEs. Assistance and advice is also provided for the migration to Linux.

Section Six - Market Analysis
This section gives an overview of the market, providing an examination of the drivers, along with an investigation of the future direction, and including a review of the approach adopted by a selection of businesses that have deployed Linux in the Enterprise.

Section Seven - Tables
This section first presents Butler Group's Features Matrix, which allows the selected Linux distributions to be seen side-by-side in terms of features and capabilities. A number of supplementary tables are also included in this section.

Section Eight - Comparisons
This section includes comparisons of the vendors and services featured in this Report.

Section Nine - Technology Audits
This section contains in-depth Technology Audits for the vendors and solutions reviewed in this Report.

These are as follows:

Computer Associates
Debian
HP
IBM
Mandrakesoft
Novell
Novell SUSE LINUX
Oracle
Red Hat
Sun Microsystems
Section Ten - Vendor Profiles
This section contains brief profiles of a number of relevant vendors and technologies not covered by a Technology Audit.