About the author: Brien Posey is a 10-time Microsoft MVP with two decades of IT experience. Source: To cloud or not to cloud: What’s your cloud migration strategy?
Here we explore factors that should guide a cloud migration strategy and help determine whether to move on-premises workloads to the cloud.
One of the first considerations is an organisation’s existing data center investment. Outsourcing a server’s data and/or functionality to the cloud may mean abandoning your on-premises investment unless an on-premises server can be repurposed.
An organisation can still benefit from migrating certain on-premises resources to the cloud even if she has invested in a lot of hardware. This is a “piece-by-piece” migration.
An organisation could integrate a cloud services roadmap into its hardware lifecycle policy. Doing so allows IT teams to migrate on-premises resources to the cloud instead of moving them to newer hardware.
The prospect of using cloud services is often particularly attractive for smaller organisations and startups because the cloud services provides access to enterprise-class hardware and fault-tolerant features that would otherwise be unaffordable. Similarly,startups can benefit from cloud services because they can get their operations running quickly without having to invest in on-premises data center resources.
Application requirements for a cloud migration
In the case of application servers, administrators must consider whether the application can function in the cloud. Likewise, the application’s performance must be considered.
Compatibility usually isn’t a big problem for newer applications that run on top of modern operating systems. It is also easy to assume that performance won’t be an issue for such applications because most cloud providers will allow hardware resources to be allocated to hosted servers on an as-needed basis. However, two major considerations must be taken into account for such applications.
- The first is performance. Even though you can provision the hosted application server with nearly unlimited compute and memory resources, Internet bandwidth may impede application performance.
- The second consideration is application portability. Although it is often easy to migrate a virtualised application server to the cloud, the application might have external dependencies that rule out (or greatly complicate) a cloud migration.
For older applications that run on legacy operating systems, a move to the cloud may not be an option. Lab testing is the only way to know how an application will behave in a cloud environment.
Another consideration for moving application servers to the cloud is hardware scalability. Cloud services are ideal for hosting hardware-intensive workloads because cloud services generally offer nearly unlimited scalability.
A cloud-based high-performance computing environment can become cost-prohibitive for going to the Cloud/
Virtualisation will ease a cloud migration
Regardless of organisational size, one of the considerations is whether the workloads targeted for cloud migration have been virtualised. In some cases, it’s much easier to move workloads to the cloud if on-premises servers have already been virtualised.
Cloud infrastructure considerations
Another factor to consider is the on-premises network. If an organisation plans to keep resources on-premises (even temporarily), the cloud network must function as an extension of the on-premises Active Directory forest. This means that the organisation will typically have to deploy cloud-based domain controllers, DNS servers and possibly DHCP servers. More importantly, the organisation will have to figure out how to establish a secure communications path between the cloud-based virtual network and the on-premises network.
It is important to keep in mind that cloud migrations are not an all-or-nothing proposition. Organisations do not have to go “all in” with cloud migrations. In most cases, it will make sense to move certain services to the cloud.