Cloud computing represents the biggest change to the way businesses deploy IT applications and services since PC client/server architecture emerged in the 1980s. However, the ways in which organisations have moved to the cloud have varied. After companies such as Salesforce had proven the efficacy of the model, a wave of initial enthusiasm for software as a service developed and, with the success of AWS a little later, the public cloud saw many companies move to ‘cloud first’ strategies as a way to radically reduce upfront costs and the administration burden in their datacentres.
However, many found that the switch was not as painted, leading to issues of dependencies, disruptions and failed workload migrations, especially where a ‘lift and shift’ approach had been applied. Another factor: ‘bill shock’ where public cloud platforms would accrete costs and often end up as highly expensive options.
That dynamic led companies to maintain open options and use the right platform for the right workload on a horses-for-courses basis. Under this hybrid IT umbrella, it’s clear that both public clouds and private clouds are here to stay and in this article, I want to argue why private cloud has become, and will remain, a critical model for modern IT application delivery.
Tasks and trade-offs
A private cloud possesses most of the features that are desirable in the public cloud such as self-service, rapid deployment and elastic compute capacity but with the direct controls, security measures and customisation familiar from traditional IT. It will typically make extensive use of virtualisation and, often, containers, to abstract resources and provide granular controls and flexibility.
The private cloud will usually need higher staffing levels than public cloud and demand the same high standards of accountability of traditional IT, with security, data governance and overall systems management falling under the direct remit of the CIO. So, upfront costs will be higher than in the public cloud, but efficient datacentres will be highly automated, homogenous by design and see the benefits of highly repeatable processes and over time could provide a platform with lower ongoing costs. The small premium in administration compared to public cloud will for most be a reasonable price to pay to claw back control of IT resources.
And there are also some advantages that may not be immediately apparent in maintaining private clouds alongside public clouds. A big one is cloud bursting where public clouds and private clouds can be wedded to accommodate spikes in demand. Take the example of a toy retailer that typically sees demand levels rise in the holidays season. Once private cloud capacity is saturated, the public cloud can kick in to soak up the extra land grab for server, storage and networking resources. The result is an overflow mechanism that operates without service interruption.
Alternatively, applications can be temporarily moved to the public cloud to free up private cloud capacity. In either case that means that the retailer is only paying for the excess capacity on a utility basis, rather than having to build private clouds with a large capacity that usually goes untapped. Well managed private clouds that have been highly virtualised and instrumented can accommodate high levels of server, storage and network utilisation without risk. This is a very different environment to the old on-premises model where servers were often operating at 20 per cent utilisation levels or even less, leaving IT buyers with a lot of expensive tin that is being under-exploited.
Another enticing option that is maturing: firms might want to move between clouds based on changing needs of workloads and their suitability to today’s cloud platforms. True cloud bursting has so far been something of a dream for IT but the ability to switch between an AWS and an Azure is becoming a reality for many as orchestration and abstraction pieces fall into place.
The time is right
Private cloud is mature and continues to grow as smart IT shops find ways to automate and monitor resources for optimal outcomes. It’s likely that the COVID-19 pandemic will see cloud adoption grow generally with the market expanding by 10.4 per cent even as IT infrastructure spending contracts by 16.4 per cent. IDC suggests that private cloud will expand from 16.2 per cent of the IT deployment pie in 2019 to 18.6 percent this year, largely at the expense of traditional on-premises IT.
Private cloud provides an example of pragmatic compromise and realpolitik where many of the respective benefits of traditional on-premises IT and public cloud computing can be retained. If private cloud is the halfway house of business IT, then it remains a highly valuable and desirable place to reside.
Hybrid and multi-cloud IT dominate today and will do for years to come as companies seek the agility to deliver services that fit business needs and respond fast to changing circumstances. Ultimately, there will be no ‘winning’ deployment model in cloud and it will never resolve to being an either/or debate. But private cloud will coexist with other models to provide the platform that delivers the comfort-factor control, familiarity and security/governance of the on-prem IT old world with the agility and rich virtualisation of the new world.