The German city of Munich will pay more than €50m if it decides to drop its custom Linux-based OS and return to Windows.

The cost of rolling out a Windows 10 desktop to about 29,000 PCs at the council was revealed by the authority yesterday.

Under the plan, the former open-source champion would pay €49.3m to prepare a new Windows 10 client for rollout, with a view to beginning the migration in 2020. The work would be carried out as part of a wider €89m overhaul of IT at the council, which would also include €3.1m spent on testing and training.

The move to Windows 10 would mark a major shift for an organization once at the vanguard of the open-source software movement. A decade ago Munich made headlines for switching thousands of PCs from Windows to Linux, at a time when a move on that scale was almost unheard of.

Munich’s switch back to Windows 10 is waiting to be signed off by the full council on Thursday, however the move is all but certain to be approved.

The council says the move to Windows 10 will make it easier to source compatible applications and hardware drivers than it has been using a Linux-based OS, and will also reduce costs by not having to run a Windows and LiMux client side-by-side. Currently, roughly one-fifth of the PCs used at the council are Windows machines, a necessity due to the some line-of-business applications only running on Windows.

“The primary goal is to harmonize clients in a timely manner so that we end up using the new Windows client throughout the city,” the council states in an official report.

While Munich says work associated with the rollout of Windows 10 would cost €49.3m, there appear to be ancillary costs, which are mixed in with the wider €89m IT program. Under this program the council would also extend the use of virtualized operating systems and carry out a trial of Microsoft Office 2016. These costs include €14m spent on staff, €24m for external advice, €13.4m on internal IT services, €4.8m on hardware, €29.9 on licenses–for Microsoft Windows, Microsoft Office, software distribution, print and profile management, identity management and related to virtualization–and €3.1m on testing and training.

The authority also lists multiple drawbacks of a return to Windows, including the need to buy licenses from Microsoft, the cost of the migration and retraining staff to use a new OS, and the loss of independence from a single software vendor, a driving factor behind the initial move to open-source software.

Under the plan, work to prepare the Windows 10 client would get underway in early 2018, with the client ready to begin rolling out from 2020 and the full migration completed by the end of 2022, possibly extending into early 2023. Until the rollout is complete in 2023, a custom version of the Linux-based OS Ubuntu, known as LiMux, will continue to be supported and used alongside Windows 10.

How the cost of returning to Windows compares to that of the original migration to LiMux is less clear, but in 2014 Munich mayor Dieter Reiter said going back to Microsoft would mean writing off about €14m of work it had carried out to shift to LiMux.

While there have been some complaints about software at the council, only a minority of staff had severe issues that they believed could be solved by migrating to Windows and Microsoft Office. And in March the city’s IT chief also said there was ‘no compelling technical reason to return to Windows’, pointing out the authority had “solved compatibility and interoperability problems” related to running software on LiMux.

Don’t miss: Munich: The journey from Windows to Linux and back again (free PDF)

The migration to Windows 10 will happen alongside a major reorganization and centralization of IT at the council, leading one insider at the council to warn it will impose needless pressure on Munich.

“I see it as really unnecessary. The problems won’t be solved by migrating operating systems because we have a working Linux system,” they said.

A major factor driving the decision to return to Windows appears to be changes in the political make-up of the council since the LiMux project began in 2003. Today the CSU political party, which has a long track record of opposition to LiMux, is also part of the ruling coalition in Munich. It was this coalition of CSU and SPD politicians that put forward the proposals to switch back to Windows 10 earlier this year.

As well as establishing a new Windows 10 client for use across the council, the authority will also have to create new infrastructure and processes to manage and update the Windows client and to handle identity assurance and access management.

Much of the software that runs on LiMux is platform-independent, reducing work needed to port software to Windows 10, according to the council’s assessment, which says existing software should be running on Windows 10 by no later than March 2023.

The council expects to take on five additional “Windows engineers” who will help migrate applications to the new client.

Going back to Microsoft Office

A proposal that Munich should also switch from the open-source office suite LibreOffice to Microsoft Office is more complicated, due to what the council calls the potential “high costs” of such a move. For that reason the council will only be asked to approve a pilot of Microsoft Office on Thursday. Under this trial, 6,000 instances of Microsoft Office 2016 would be run on virtual machines, to assess the costs and the technical barriers to a wholesale move to Microsoft Office. There are indications that a full rollout of Microsoft Office 2016 could be even more expensive than the return to Windows, with one report suggesting the combined cost with the Windows migration could be higher than €100m.

Those familiar with IT at the council have said the move to Microsoft Office 2016 would be particularly challenging, due to staff relying on thousands of LibreOffice templates and macros that would have to be converted, alongside the development of a new templating system.

“There is a custom templating system called WollMux, which obviously doesn’t work with Microsoft Office. There are tens of thousands of templates associated with WollMux, and all of those would have to be migrated,” said a Munich insider.

The results of the Microsoft Office pilot will be assessed by an external auditor, who will present their findings to the council by the end of 2018. If the move to Microsoft Office does go ahead, it is not expected to be completed before the end of 2023, with the council saying it will necessitate the migration of what are “sometimes very complex tables and macros”.

Even the council warns that staff expectations may have to be managed during the migration to Windows 10 and reorganization, to help stave off a user backlash against disruption to IT at the council.

“The new IT organization is only just beginning to find its feet, and the newly defined processes first have to be implemented, which can temporarily reduce the performance and overall available capacity of the IT,” it states.

“So if the measures are going to successfully implemented, it’s important from the outset that they’re accompanied by targeted expectation and change management to reduce negative effects and minimize the consequences of the reorganization.”

Under proposals for the future of IT at Munich, the council also wants to significantly increase the number of applications that are run on virtualized infrastructure or in web browsers. By creating these “platform-independent” applications, the council believes it could reduce the time it takes to test and update clients.

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