What is Downtime (cloud service)?

Downtime is a period of time in which the service is unavailable or not working due to unexpected circumstances such as outages, maintenance activities or updating periods.

With the advent of virtualization and cloud computing services, a consistent and all-round service is a necessity. Customers who are looking for cloud services would only be convinced if the cloud solution is promised to perform better instead of an on-premise solution. Downtime or availability is considered to be one of the most important factors to consider when implementing a new cloud service to the solution lineup.

Causes of service downtime

There are hundreds of ways that things can go wrong that can cause service downtime. According to this mlytics blog article, some of the most common ones are:

  • Hosting provider limitations and failures
  • Expired domain or hosting agreement
  • Human error
  • Traffic overload (DDoS) attack

And some of the technical (advanced) causes are:

  • DNS Failures
  • Malicious attacks
  • CDN failures

For an in-depth explanation and solution to each cause, please see our blog article: “Website downtime causes and solutions: what other articles didn’t tell you”.

Downtime and SLA

Cloud solution providers usually have a scoped uptime/downtime tolerance range included in the internal or external service level agreements (also known as SLA’s). 

This is imperative for customers since service unavailability might cost them thousands or even millions of dollars. To put things into perspective, a mere sixty minutes of downtime could cost Amazon several million dollars of revenue. 

The impact caused by downtime

Not just revenue, the reputation of a company can also be impacted by downtime, which  may cost consumer confidence on different levels of magnitude depending on how the situation is being handled. A single allegation tweet or news regarding the degradation in service of some company could negatively impact the business and its overall revenue streaming capabilities.  Therefore, it is usually seen that companies that deal with such clients also possess multiple alternative resources to continue providing their services without interruption even if there is a shortage or an outage.

Availability Percentage Calculation (Source: https://en.wikipedia.org/wiki/High_availability)