On-Premise vs. Cloud IaaS: Advantages and Disadvantages

It’s widely known there’s a lot of info about the pros and cons of cloud tech. Usually, it emphasizes the benefits, not the drawbacks.

The info below isn’t the ultimate truth and doesn’t cover everything. It mainly looks at Infrastructure as a Service (IaaS), comparing the good and bad of on-premise and cloud solutions.

Advantages of the Cloud, Disadvantages of On-Premise

When transitioning to the Cloud, you can forget about the following concerns:

No need to manage the physical IT infrastructure of the data center, including:

• Server hardware and replacing faulty components
• Backup power sources (UPS), maintenance of diesel generators, or battery replacements based on the data center size
• Network components: routers, switches, modules, cables
• Storage (Storage Area Network), eliminating discussions on RAID configurations, aggregates, and disks. No debates on iSCSI, FibreChannel, or InfiniBand. Complete transition to All-Flash-Arrays or a partial one?
• Backup systems and data storage
• Information security

The listed hardware not only requires regular updates but also replacements after the lease or warranty period (3–5 years). No need to engage in discussions about which manufacturer to order hardware from.

1. Cooling system for the data center
2. Fire suppression system and early fire detection
3. Physical security organization for the data center
4. Expansion possibilities (adding new cabinets), along with related changes in cooling and fire suppression systems.

It’s worth noting that in terms of security, whether physical or informational, a serious cloud provider significantly surpasses the average enterprise.

Personnel and Expenses

All the mentioned categories have their own management systems, requiring qualified support staff. When transitioning to new technologies, employees also need training.

The Cloud helps reduce expenses, especially in terms of engaging external resources in projects primarily related to replacing or updating existing infrastructure.

From a tax perspective, the Cloud is attractive since capital expenditures (CAPEX) for equipment purchase transform into regular operating expenses (OPEX), which is more advantageous.

And finally, forget about electricity costs.

Scalability, Automation, Innovation

The ability for rapid, automated scaling or downsizing of infrastructure can be considered a primary advantage of cloud technologies. Use and pay only for what you truly need (Pay-As-You-Go).

Major cloud service providers are constantly searching for additional services to offer clients or ways to reduce their own expenses.

Disaster Recovery

In terms of creating uninterrupted infrastructure functioning and ensuring post-disaster recovery, the cloud has undeniable advantages.

Disadvantages of Cloud, Advantages of On-Premises

In many cases, the aforementioned advantages easily turn into drawbacks.

Let’s start with the data center itself. Any reasonably serious mid-sized business already has its own data center. So, you already have a secure facility with a fire suppression system, uninterrupted power supply, and cooling in place. Your data center is likely equipped with enough cabinets filled with corresponding equipment (servers, storage, switches, backup libraries).

Purchased server equipment allows for easy upgrades, like adding extra memory, and decommissioned servers can be repurposed for creating a testing environment.

It’s hard for me to imagine that all the mentioned equipment was bought simultaneously and has the same warranty period. Transitioning to the cloud might be a well-considered step only after this period.

Over the years, many components have become significantly more efficient, from processor energy consumption to data transmission speeds exceeding 40 GB or more, and All-Flash-Arrays Storage. Often, just replacing Storage Area Network (SAN) can significantly “unload” (save space, reduce electricity expenses) a data center, increasing its efficiency. I recall from personal experience using PureStorage All-Flash-Arrays, occupying 6U, which replaced a fully-packed 42U NetApp cabinet.

The claim that abandoning local infrastructure means losing investments is valid.

Trust and Reliability

Trust in the provider is, in my opinion, the most critical criterion for evaluating cloud technologies.

You must be confident in:

1. The inviolability of your data.
2. Quick, loss-free recovery in case of special circumstances.
3. Full compliance with local legislation.
4. Professionalism of the staff.
5. The services being of much higher quality or at least equal to what you had before.

Having various security compliance certificates can’t guarantee actual safety.

Are you sure that in case of losing one of the two regional data centers, your provider can ensure the full functionality of your entire infrastructure? Is its scalability, especially during peak business periods, the main concern? I’m not sure, are you?

A colleague once told me that the possibility of losing one regional data center is as improbable as meeting a dinosaur on the street. However, who in New York on September 10, 2001, would have believed that one of the city’s symbols would no longer exist by tomorrow afternoon? A significant data center can undoubtedly be a target for “unpleasant individuals,” as its loss can cause not only serious economic damage but also far-reaching consequences. The cloud is when many companies put their eggs in one big basket and hope it’s never dropped. Each egg is a kind of Egg of the Immortal Koshchei. Dilute it, and you jeopardize the viability of its owner.

As far as I know, changes in U.S. legislation now allow demanding compensation of up to $100,000 per user in the event of data theft due to the provider’s fault. In this context, the word sabotage takes on a new meaning. No matter how carefully personnel selection is conducted, people are not perfect and susceptible to flaws, such as greed, for example.

Disaster Recovery for Local Infrastructure

The capability of post-disaster recovery, coupled with flexibility and scalability, is one of the primary arguments in favor of the cloud. With cloud technologies, it’s relatively straightforward to create a duplicate of your infrastructure located hundreds of kilometers away from the main data center. Do you currently have similar solutions, backup systems? Are they genuinely necessary if you’ve been without them for many years?

Internet Connectivity

One of the key conditions for the successful implementation of cloud technologies is having a fast and reliable internet connection, with the mandatory ability to increase speed and bandwidth. Unfortunately, many underestimate this factor, leading to less than successful project implementations.

Cost

So, let’s be honest; virtual machines in the cloud aren’t particularly cost-effective. If we set aside the additional benefits that the cloud undoubtedly provides (especially in terms of Disaster Recovery), the cost of VMs in the cloud significantly surpasses the cost of VMs in a local data center.

Conclusion

On-Premise is when you have the freedom of choice, like a tailor-made suit crafted just for you that fits perfectly. Cloud, on the other hand, is an attempt to find a suitable off-the-rack suit from a vast assortment of high-quality options. A Cloud Provider must deliver identical services to all its clients without any special conditions.

If migrating to the cloud is a complex process requiring deep and meticulous planning, reverting infrastructure from the Cloud to On-Premises is an even more intricate and incredibly costly task. A complete transition to the cloud is a one-way ticket.