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Windows Server is the unsung hero of Microsoft’s operating system line-up.

While Windows gets all of the accolades, Windows Server is something of a hidden workhorse, especially for businesses.

If you have an on-site network based on a Windows network, there’s a good chance you also have a server with a flavour of Windows Server running on it.

While server operating systems do have very long product lifecycles – 10 years on average – it’s also easy to miss these key dates. With that in mind, let’s consider one particular version of Microsoft’s server OS, Windows Server 2012 R2, and its upcoming “true” end-of-life status.

What do mean by that? And what’s the difference between mainstream and extended support?

Let’s find out.

When does Windows Server 2012 R2 go end-of-life?

Unlike its higher-profile software offerings, like Microsoft 365, Microsoft has a specific lifecycle for its Windows Server products.

More specifically, these operating systems are released under what’s known as Microsoft’s Long Term Servicing Channel (LTSC). In a nutshell, this means that each product is supported for 10 years: the first 5 of which are known as mainstream support, and the second 5 known as extended support.

Microsoft Server 2012 R2, having originally been launched in October 2013, completed its mainstream support phase in October 2018. At this point it technically became an “end-of-life” product, because it was no longer being fully supported or feature-enhanced by Microsoft.

As of October 2018, Server 2012 R2 entered its “extended support” phase, which will end in October 2023. But what does that really mean?

Mainstream Support vs. Extended Support

To define extended support, we also need to define mainstream support.

The key difference between the two different phases of Microsoft’s product lifecycles under the LTSC program are the level of support customers receive.

Here’s a simple breakdown of mainstream support vs. extended support for products such as the Windows Server range of operating systems:

  • Mainstream support is essentially the glory days of a Microsoft product. It’s the first 5 years of the product’s lifespan and it’s being continually updated with new features, service packs, updates, fixes, and more. Microsoft also offers real-time support (i.e. phone support) during this phase. The earlier you invest in a product during its mainstream support phase, the more you’ll get out of it in the long-term – up to a decade, if you play your cards right.
  • Extended support refers to the latter 5 years of product support per the LTSC system. It’s no longer the focus of the Microsoft team, and will likely have been succeeded by at least one more product in the meantime. During extended support, customers will only receive critical security updates and reliability patches. Non-security hotfixes will not be delivered unless the customer has an extended support agreement with Microsoft – and that comes at a cost.

What happens when Extended Support ends?

The most important thing to remember about extended support is that, once it’s expired, the product will be almost entirely unprotected by Microsoft. Even Microsoft themselves are clear and open about the risks of running a product beyond its end-of-life roadmap.

So, after October 2023, Windows Server 2012 R2 will no longer receive any security updates or critical patches for key exploits. You won’t even be able to pay for support anymore, as you can during extended support – the product is simply unsupported going forward.

The problem for businesses? Well, it’s almost certain that cyber attackers will be waiting patiently for the product’s extended support to end, at which point they will do all they can to find exploits.

If you continue running the server operating system, you’re exposing your data and your network to potential breaches.

Not sure about your business hardware’s lifecycle? We can help

If you’re operating a server without a dedicated IT resource and you’re unfamiliar with the ins-and-outs of server operating systems (don’t worry, not many people are), you might be unsure about how long it has left. Or perhaps you’re running Windows Server 2012 R2 and you’re concerned about the end of support on the horizon.

Either way, at Oakland Associates, we offer comprehensive IT support agreements which include full IT hardware roadmaps, so we know exactly how much life your hardware has left on the clock.