Virtualization – a solution for all environments?
Virtualization technology is not new – it has been a mainstream IT capability for about two decades, since the early 2000s. So much so that, for most workloads — whether development, QA, or production — it is often the default choice for companies of all sizes across multiple industries.
The benefits are widely known. Consolidation and enhanced server hardware asset utilization lead to lower purchase, setup, power consumption, and cooling costs. Increased flexibility and agility in terms of running multiple operating systems and applications. Restoring VM backups, reverting to VM snapshots, and achieving lower planned and unplanned downtime by clustering the servers hosting VMs. And let’s not forget the ability to migrate VMs to and from both public and private clouds.
This technology can now be considered mature. Earlier concerns around server hardware compatibility and validation by hardware vendors for hypervisors, stability, and performance overhead for VM workloads have all largely been addressed. So, why not use it everywhere, including at the retail edge, including convenience, fuel and retail customer stores and sites serving the public?
The simple answer is that virtualization technology was never really designed with a retail edge environment in mind. The focus has been on scaling up and out — bigger servers and more of them in a cluster, with hypervisors able to use all the RAM and CPU, running bigger VMs in a monitored datacentre environment. That also means redundant power supplies and cooling, UPS and generator backups. And highly redundant SAN for shared storage, 10Gig LAN network links, redundant fast WAN links, and a dedicated IT team using complex and sometimes expensive hypervisor management technologies to get even more out of such a setup in the areas of live migration, nested virtualization, and other advanced capabilities.
The retail environment, however, is often the exact opposite. Space and cooling capacity is limited, a UPS cannot be assumed, and power supplies are often erratic. WAN links are slow and regularly drop out. The environment is hostile — the physical security of the IT estate, often implicitly assumed in most IT setups, is weak. Power and network cables are prone to be disturbed. Therefore, virtualization at the retail edge requires a completely different approach than a data center or server room.