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Moving from legacy IT to a private cloud

Private and public clouds are accelerating the transition away from legacy IT

I think most IT professionals agree that the cloud has changed the ground rules for operations. The main challenge to legacy IT is that the acquisition cost for the cloud is near zero.

This has created an atmosphere of inevitability for legacy installations. There really is no justification for the legacy approach to continue as it has in the past, but the multi-million dollar question is how to get from a legacy base to some form of cloud. This isn't simple. If it were, we would have done it already.

There are two issues that serve as roadblocks away from legacy IT. The first is replacing all those legacy applications, often written in-house or with custom tweaks assembled over years of operation. On the one hand, the programming team doesn't want to let go, and on the other, there is no way to find a 1:1 replacement written on a modern code base.

The other challenge is figuring a path forward that allows the mass legacy applications to be dismantled. This is no minor task. Over time, legacy applications tend to get very intertwined and tangled.

The result is that most CIOs with a large legacy investment look to hold out with the status quo until they reach retirement.

Unfortunately, CEOs and CFOs are looking for two things legacy IT can't bring to the table, namely agility and low cost of operation. So what is a legacy shop to do? There are two parts to a replacement roadmap. Dismantling the legacy monolith is a process that takes place from the outside surface and simultaneously from the core.

This is because many larger legacy setups are a combination of legacy applications and commercial off-the-shelf packages. Consider these segments private cloud candidates, especially if their hardware platforms are getting long in the tooth. Moving them to a private cloud model allows an automated virtual environment to optimize the workloads and provide the needed agility to keep the business vibrant.

In many ways, though, we've dodged the hard issue in dealing with legacy IT. At some point, likely sooner than later, the core applications have to be migrated to modern platforms. The public cloud is increasing the pressure to do that enormously. This is where the roadmap to complete the transition becomes important.

Most companies are choosing a hybrid cloud approach, given that it keeps control and local interfaces for the legacy apps, and for the commercial software surrounding them. The process of transition will be one of migrating chunks of functionality to the private part of the hybrid cloud, while free-standing apps and code sets that are ready can migrate first to the private cloud, and then to the public cloud as desired.

At some point, a decision will have to be made to turn off the core applications and replace them. This will involve more massive changes to in-house business processes than the earlier migrations, so a lot of planning across business functions will be needed to implement a successful move.

The endpoint of the migration will be different case to case. Many users will choose to adopt software as a service (SaaS), and much of the operations will eventually migrate to public clouds. This is an economic decision, but SaaS has strong cash flow and agility arguments behind it.

With such a huge gap between business models, ranging from hardware to license fees to support and programing teams, private and public clouds will force legacy replacement at a much faster pace. We are seeing that already in cloud uptake in the U.S. government, which most of us would have considered legacy's last refuge.

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