With modern cloud hosting providers, is it possible to achieve 100% uptime?

When a cloud service goes down, it makes big headlines. Many businesses now depend on cloud hosting services to always be on. Despite that desire for constant connectivity, no cloud providers actually promise 100% uptime. Is such a thing even possible? There is no simple answer, but there are many issues at play here.

Most web hosts will offer 99% uptime or something close to it, leaving the window open for possible downtime. Some downtime may be intentional and others might not. The following are a few examples of unavoidable downtime:

• Hardware upgrades
• Scheduled maintenance, especially security updates that require server reboots
• Power outages. Often times these can be redirected to redundant servers, but not always
• Security attack. A denial of service (DoS) attack or other major intrusion can cripple even the most advanced servers
• Internet congestion or delays – Yes, I am going to use that old analogy. The Internet is like an “information superhighway”, and a road block or other problem at any point can cause a disruption of service. This may have nothing to do with your web host or your Internet service provider but rather one of the junctions in between the two.

Any one of these events or other unavoidable acts of nature can cause stoppage of cloud service or any web hosting for that matter. In other words, with our current technology, 100% uptime is probably just not feasible. What a web host can promise, however, is that schedule downtime will be during off hours, preferably when you and your customers are asleep. Moreover, they can promise that any unintentional down time is mitigated quickly and that they compensate you for any loss if it is not.