In times of growing digitalization, it is almost impossible for companies to operate without Internet availability and the right business software. Therefore it is very serious when a network component or even the entire IT infrastructure goes down. Even short downtimes can result in high costs and annoyed customers – another reason to tackle the topic of high availability in one’s own company.
The importance of high availability has already been deeply rooted in the corporate awareness of large companies. Small and mid-sized companies, however, still often put the topic into cold storage due to time and costs. A big mistake, considering that longer network and database downtimes can, in critical cases, even threaten the continued existence of companies. The aim is to keep systems available even if one or more components relevant to the company go down. Only after it is already too late and components of the infrastructure are already down, most companies usually first realize the importance of high availability. However, not only sudden failures of the systems or individual components, but also planned downtimes, for example in the case of necessary maintenance work, should be considered.
Different levels of high availability
A system can only be classified as highly available if it manages to achieve more than 99.9% availability in 24/7 operation. Downtime is thus reduced to less than 8.5 hours over the course of year. Adding further decimal places subsequently increases availability. According to this, an availability of 99.9999 % means a much shorter downtime of around 32 seconds in a year. This classification form also serves as a benchmark for highly available systems on the IT market.