The French gendarmerie began its switch to Linux almost 10 years ago: plans to expand the use of productivity tools in the force while at the same time keeping a lid on costs meant that proprietary software was given the boot.

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In 2004, the gendarmerie — France's military police force — announced it would begin moving thousands of PCs from Microsoft Office to OpenOffice , and adding the open source suite to new PCs: from a base of 20,000 Microsoft Office-equipped machines, the gendarmerie intends to have 72,000 on the open source equivalent by the time the migration is complete next year.

2005 also saw the gendarmerie switch its default browser from IE to Firefox , and start using Thunderbird for email. By 2007, GIMP and VLC had also made it onto gendarmerie PCs.

But it didn't stop there. In 2008, the OS was targeted for an open source transition, with Ubuntu in the frame. At first, 5,000 PCs were transferred over as a test rollout — described as the "handcrafted phase" — and in the years that followed, the "industrialised phase" started, as another 30,000 or so made the change.

According to squadron leader Stéphane Dumond, of the French interior ministry's technology and IS services department, there are now 37,000 PCs running GendBuntu, the organisation's Ubuntu LTS distro featuring gendarmerie-specific apps, and there will be 72,000 by the time the rollout is complete next summer.

This last phase of the project marks a massive acceleration in the pace of the rollout, prompted by the looming deadline for the end of XP support . When plans for migration were first drawn up, the Ubuntu deployment was supposed to be completed by 2015. However, with Microsoft ending support for XP in April, the thousands of machines still running the antique OS will be shifted to GendBuntu by the middle of 2014.

Lower TCO

According to Dumond, the toughest part of the migration as a whole has been resisting the siren song of proprietary software: the challenge was "maintaining the main strategy during so many years (from 2004 to now) against sweet temptations to choose the easier (but with higher costs) way".

Higher costs indeed — the organisation estimates that the TCO of the desktops will fall by 40 percent between 2008 and 2014 when the deployment is complete.

Part of the TCO reduction comes in upfront costs: savings on licences and cost of licence access, and, when it comes to hardware purchasing, the force can buy desktops without an OS already installed, saving €100 or so per PC.

However, the savings aren't just from software licences costs: the change has also meant a reduction in local tech support needed, while Canonical charges the organisation €1 per machine per year to provide support.

Managing the fleet it easier too, Dumond says: for example, any upgrade from one LTS version to another is driven by the central IT team via the WAN with minimal disruption to officers on the ground, as happened earlier this year when the 37,000-strong fleet was moved from 10.04 to 12.04.

But, says Dumond, when looking at costs, it pays to remember that being free from the whims of commercial software vendors "is priceless".

For all its cost savings, the shift to open source has not been without resistance, both from staff and vendors. It's "a daily fight against internal and external resistance", according to Dumond. "Internal because some of our project managers are likely to forget that we are migrating to Ubuntu and external because we have to force companies (like SAP, for example) to provide full Ubuntu-compliant software if they want to win our calls for tender."

To help minimise disruption, the apps were kept consistent between the Windows and GendBuntu desktop. The gendarmerie also worked out an additional measure to sweeten the pill for the average user having to move from their familiar Microsoft environment to the brave new world of GendBuntu: throw in some new hardware.

"We added a bonus: each Ubuntu computer came with a new widescreen [monitor], so the change was more easily accepted with such an item," Dumond tells ZDNet.

There has been a drop in helpdesk calls from users, he added, but it's one which he attributes to the relative age of the machines: Ubuntu desktops tend to be years younger than their XP counterparts.

The migration risks

The project, along with the City of Munich's migration of 13,000 Windows PCs to a custom build of Linux, has been one of the trailblazers of wholesale moves to open source software. But when the gendarmerie began its own transition, there were few case studies for migrations on such a scale.

It was, says Dumond, "a huge risk".

"We bet that the change would not be so important, not for end users (we were quickly right!) but for technical teams (central or decentralised ones). We were right [there] too," he says, but notes that the 800 local IT staff were each given two weeks training to make the migration smoother.

While the proposed move of 35,000 desktops in under nine months may seem a tough one, Dumond says that in reality, it wasn't so daunting: with 5,000 LANs, it's a really only a case of moving a few PCs per LAN.

Each LAN has already had at least one machine on it transferred to Ubuntu, during the 'handcrafted phase' in order to introduce new services, including file sharing, and to show police officers that the change might not be as dramatic as they might fear.

While the gendarmerie may be quickly becoming known as an Ubuntu shop, it still plans to retain thousands of Windows machines after the migration is complete next year.

The organisation is made up of 90,000 or so users, and around 72,000 will have Ubuntu PCs and 13,000 Windows desktops (not every staff member needs their own machine — some police officers share them).

"We are not dogmatic, but pragmatic: you can't bypass a Microsoft OS in this globalised world where the market share of Windows is 90 percent. So, unless this changes, I will need such an OS on some computers. The challenge is to reduce them to the minimal number," Dumond says.

The gendarmerie is now looking at whether the same strategy could be deployed in the mobile sphere. It's considering a corporate device rollout in future, and is looking at both Android and Ubuntu Touch as potential candidates for a mobile OS.

If it goes with Ubuntu Touch, it may follow the same path as it has done with desktops: take hardware bearing another OS and install the Ubuntu equivalent over the top, given no handsets running the OS natively are known to be in the works.

"This is the next step: the mobility challenge," Dumond says. "We have not made a choice of a technology yet, but Android and Ubuntu Touch are the focus."

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