A full move to cloud datacenters means replacing your physical servers with rented computing power, but it requires more than just signing a contract

Moving entirely to cloud datacenters means shutting down your own servers and running everything — applications, databases, storage, backups — through providers like Amazon Web Services (AWS), Microsoft Azure, or Google Cloud Platform. It sounds straightforward until you start counting what has to change: your team's skills, how you manage data, which applications can actually move, what compliance rules apply, and how much you'll actually spend once you account for everything.

The real work is not the migration itself. It is the months before, when you figure out what can move, what cannot, and what needs to be rebuilt entirely. Organizations that move fastest are the ones that start by auditing their current setup — not by rushing to move everything on day one.

Key Takeaways

  • You need an inventory of every application, database, and service running on your servers, including which ones were built for cloud and which ones need rebuilding.
  • Your team must learn new tools and ways of working — cloud administration is different from managing physical servers, and this training takes months, not weeks.
  • Some applications cannot move without significant rewriting, and deciding which ones to rewrite, retire, or replace is the longest part of the process.
  • You must understand your actual cloud costs before you commit, because per-gigabyte pricing and always-on services can exceed what you paid for servers.
  • Data security, compliance, and backup strategies all change in the cloud and must be redesigned before you move sensitive information.

Auditing what you actually have to move

Before you can move anything, you need to know what exists. Most organizations discover during this phase that they have applications nobody remembers building, databases running on servers that were supposed to be decommissioned five years ago, and custom scripts that run critical processes but exist only in one person's head.

Create a spreadsheet with every application, database, and service: what it does, who uses it, how much data it holds, how often it runs, and whether it was built in-house or bought from a vendor. For each one, note whether the vendor supports cloud versions or whether you would need to rebuild it yourself. This is not a one-week project. Most organizations need two to three months to get an honest picture.

As you build this list, you will find applications that are no longer used but still running, databases that could be consolidated, and services that could be retired entirely. Removing these before you move saves money and complexity. A cloud migration is a good time to clean house, but only if you do it deliberately.

Deciding which applications can move and which need rebuilding

Not all applications move to the cloud the same way. Some are cloud-native — built from the start to run in cloud environments — and move easily. Others are legacy applications — written for physical servers, tightly coupled to specific hardware, or dependent on old operating systems — and require significant work.

Applications fall into rough categories. Lift-and-shift applications can move to cloud virtual machines with little or no change — you are essentially renting a server instead of owning one. Refactored applications need some rewriting to take advantage of cloud services like managed databases or load balancers, but the core logic stays the same. Rebuilt applications need to be written from scratch to work in the cloud, usually because they depend on hardware that does not exist in cloud environments or because they were designed for a single server and now need to run across many.

A vendor-supplied application might have a cloud version, but it might cost more than your current license, require a different contract, or not support your current customizations. You have to check with each vendor individually — there is no shortcut here. Some organizations discover that moving to the cloud means paying for new software licenses, which can eliminate the cost savings they expected.

Building the technical skills your team needs

Cloud administration is not the same as server administration. Your team needs to learn new tools, new ways of thinking about infrastructure, and new ways of troubleshooting problems. AWS, Azure, and Google Cloud each have their own interfaces, their own naming conventions, and their own ways of managing networks, storage, and security.

Most organizations need to hire people with cloud experience or spend months training existing staff. Certifications like AWS Solutions Architect Associate, Azure Administrator, or Google Cloud Associate Cloud Engineer are common starting points, but they teach concepts, not your specific setup. Your team also needs hands-on experience with your chosen provider before you move production systems.

Budget for training, for hiring, and for a period where you have both old and new expertise on staff at the same time. Many organizations hire a cloud architect or consultant for the first six to twelve months to guide the migration and train the team. This is an expense, but it is cheaper than migrating badly and spending months fixing problems afterward.

Understanding cloud costs before you commit

Cloud providers charge for what you use: compute time, storage, data transfer, and dozens of other services. This is different from owning servers, where you pay upfront and the marginal cost of running one more application is nearly zero. In the cloud, every service has a price, and costs can surprise you.

A server that costs you $5,000 to buy and $500 a month to run might cost $800 a month in the cloud if you size it correctly — but it might cost $2,000 a month if you do not optimize it, or if you add backup services, monitoring, and redundancy. Data transfer out of the cloud (called egress) is expensive; moving data in is usually free or cheap. If your application downloads large files frequently, that cost adds up.

Before you migrate, run a cost analysis with your cloud provider. Most offer calculators where you input your current setup and get an estimate. But estimates are not reality. Many organizations find that their actual cloud bill is 20 to 40 percent higher than the estimate because they did not account for all services, or because they sized resources conservatively to avoid outages.

Some organizations use reserved instances or savings plans — you commit to using a certain amount of compute for one or three years and get a discount. This can cut costs by 30 to 50 percent, but only if you actually use what you reserved. If your needs change, you are stuck with the commitment.

Redesigning security, compliance, and backups for the cloud

Your current security setup — firewalls, access controls, backup procedures — does not translate directly to the cloud. Cloud providers handle some security (they manage the physical servers), but you are responsible for everything else: who can access what, how data is encrypted, how you back up critical information, and how you meet compliance rules.

If you handle sensitive data — health information, financial records, personal information — you need to understand how cloud providers meet regulations like HIPAA, PCI-DSS, or GDPR. Some providers have certifications for these; some do not. Some regions have data residency rules that require your data to stay in a specific country, which limits which cloud providers you can use.

Backups in the cloud work differently than on-premises backups. You cannot plug in a tape drive. Instead, you use cloud backup services, which cost money and take time to restore. You need a backup strategy that covers what happens if your cloud provider has an outage, if your account is compromised, or if you accidentally delete something critical. This strategy should be in place before you move data.

Planning the actual migration and cutover

The migration itself — moving data and applications from your servers to the cloud — can happen in different ways. A big bang migration moves everything at once, usually over a weekend. This is fast but risky; if something goes wrong, you have no fallback. A phased migration moves applications one or a few at a time, which is slower but lets you catch problems before they affect everything.

Most organizations choose phased migration: move non-critical applications first, learn what works and what does not, then move critical systems once the team is confident. This takes longer — six months to two years depending on size — but it reduces the risk of a catastrophic failure.

You need a rollback plan for every application: if something goes wrong after you move it, how do you get back to the old system? This means keeping your old servers running in parallel for weeks or months, which costs money but buys you safety. Some organizations keep a full backup of their old environment for a year after migration, just in case.

Frequently Asked Questions

Can we move to the cloud without replacing our current applications?

Yes, through lift-and-shift migration — you run your existing applications on cloud virtual machines instead of physical servers. This is the fastest way to move, but it does not take advantage of cloud features like managed databases or auto-scaling, so you may not save money. Many organizations do this first, then refactor applications later.

How long does a full migration actually take?

It depends on size and complexity. A small organization with simple applications might move in three to six months. A large organization with hundreds of applications, complex integrations, and strict compliance rules might take two to three years. Most organizations underestimate this timeline by 50 percent.

What if we cannot move some applications to the cloud?

You keep them on-premises or find a different solution. Some organizations run a hybrid setup: some systems in the cloud, some on their own servers. Others retire old applications instead of moving them. The decision depends on cost, compliance, and how critical the application is.

Do we have to move everything to one cloud provider?

No. Some organizations use multiple providers — AWS for some workloads, Azure for others — to avoid being locked into one vendor or to meet specific compliance rules. This adds complexity but gives you flexibility. Most organizations start with one provider and add others only if they have a specific reason.

What happens to our IT staff when we move to the cloud?

Their role changes, not disappears. Instead of managing physical servers, they manage cloud infrastructure, monitor costs, optimize performance, and handle security. Some staff may need retraining; some may not fit the new role. Most organizations need to hire cloud specialists while keeping experienced staff to bridge the old and new systems.