Usually when you need to do it many times at scale, self managed rack can be cheaper than cloud. The downside is requiring expertise to manage and maintain it.
The cost of deployment into the cloud is $0 at a scale that is unfathomable to any rack with the overhead being a near zero as well. Initial capital investment for the cloud is $0 as well.
The self-managed rack:
1. Has to exist somewhere.
2. Therefore it required the initial capital investment at some point, which is a mid five figure amount or more.
3. Scales by its weight, height, depth and hardware specifications.
4. Does not scale beyond (3) – hardware constraints of blades deployed in the rack are very rigid.
5. Has to have available processing capacity to support the new workload.
6. Has a habit of running of capacity at the most inconvenient moment requiring, well, a new rack.
A new/extra rack:
1. Has to be paid for from a budget. The budget may or may not exist when the new rack is required, therefore potentially incurring further, potentially lengthy, delays (i.e. «no money in the budget until the next financial year». Boom.).
2. Has to be taken through the procurement. Depending on the organisation and its size, procurement can take anywhere in between 3 and 12 months.
3. Has to be in stock.
4. Has to be installed, deployed and configured.
5. Requires technicians and engineers to be available within a designated time slot to complete (4). The technicians and the engineers (all of them or a single/few) may be unavailable due to X, Y or Z.
Bonus points:
1. The DC may not have enough room / power / cooling / etc. You and your rack are now stuck for an non-deterministic amount time.
2. Adding a new rack to your rack HA setup requires a new network interconnect due to the network capacity reaching a saturation point. It is called «an expensive network switch». Add further delays, repeat all steps required to procure a new rack, add new/unforeseen delays.
With the above in mind, I fail to see how the overhead of a poorly scalable, self-managed rack is lower compared to a $0, software driven code deployment into the cloud at a scale that is limited by the size of one's wallet.
Ah yes, the cloud, where network interconnect issues simply do not exist, and extra capacity is always available, and the budget never runs dry, and configuration is not required, and technicians and engineers are always available.
Can I have a puff of whatever it is you smoked to reach this cloud?
Your comment is inflammatory but you're not wrong. Selling the cloud as $0 cost to set up is at best, a fairy tale and at worst, an ad.
If "the cloud" was so simple, there wouldn't be 6-7 figure job positions dedicated to just setting up and managing their complexity and they definitely wouldn't come with certification requirements. Somehow the requirement of having a small team of employees "who can manage our own infra" is a deal-breaker but having a team of AWS Solution Architects is not.
