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IT administrators who combine virtualization with a server consolidation project plan can improve server utilization and reduce data center power consumption and hardware costs. A server consolidation project plan can include one of two consolidation methods: migrating workloads to a server's OS or using virtualization to run applications inside of VMs.
Virtualization is often the preferred choice for server consolidation because it introduces a host of benefits, such as reduced power and cooling costs, as well as high availability for workloads. To achieve these benefits, admins must formulate a server consolidation project plan that aligns with their business needs.
The basics of server consolidation
Server consolidation is the process of reducing physical servers in a data center. If a data center underutilizes server hardware, then admins can configure servers to host multiple workloads. This means servers can better utilize hardware, which reduces the total number of servers required to run workloads.
Benefits of server consolidation include reduced hardware maintenance costs and the overall data center footprint, which is beneficial for organizations that lease space in a colocation facility.
Admins should consider several factors during the early phases of their server consolidation planning process. For example, admins should outline specific goals, determine whether one consolidation method is better suited to achieve those goals, devise a plan to deal with possible security and compliance violations, and consider whether the cost savings justify the total expense of the server consolidation project.
A quick guide to server consolidation
There are two main ways admins can consolidate servers. First, admins can run multiple workloads on a server's OS. This technique is the simpler of the two methods and only requires a single OS license.
The primary disadvantage of this method is workload interference. For example, if a single application has a security vulnerability, then the application can act as a point of entry for malicious attackers to breach adjacent applications on a server. In addition, if a server was to suffer an outage, then the outage would affect all of the applications on that server.
The second method of consolidating servers is through virtualization. When admins use virtualization, the physical server takes on the role of a virtualization host. Applications run inside of VMs with their own OS, which helps isolate workloads from one another. A security breach within one virtual server typically doesn't affect another.
One of the main advantages of virtualization is that admins can enable fault tolerance. A fault-tolerant system monitors a data center's CPU, motherboard, I/O subsystem, power supply, memory cards and network components for failures. For example, in the event of a host server failure, fault tolerance enables VMs to fail over.
But virtualization is often expensive and complex to implement because virtualizing a data center requires new or additional pieces of hardware or software. Virtualization also makes it easy to deploy large numbers of VMs, which can deplete a data center's resources.
Refine a virtualization project plan with server consolidation
In most cases, virtualization is the preferred tool for server consolidation. Even so, there are several factors admins should consider during the virtualization project planning process. One of the first factors is data center capacity.
Admins might have a specific number of physical servers they want to keep after consolidation, so they must consider whether that number exceeds data center capacity. Virtualization infrastructure requires adequate capacity to run critical workloads, even if one or more hosts were to fail. Admins should also have extra capacity on hand to host future workloads.
Another key step is to decide which virtualization architecture to use, such as Hyper-V or VMware. Admins must then decide how many server nodes to include in a cluster and choose a storage architecture.
As admins progress through this process, they should keep an eye on the project's cost. Hypervisor licensing is one of the first costs to consider, but admins might also require supplementary management and monitoring tools, or capacity planning and management tools. In addition, admins might require a support contract depending on which virtualization platform they choose.
Finally, admins should consider how to migrate their workloads to a virtualized system. Options vary by workload, but the migration process should be seamless and avoid service interruptions.