What does the 'Five Nines' refer to in high availability? Five backup servers 9 servers working simultaneously Five levels of security 99.999% system uptime

'Five Nines' refers to 99.999% system uptime in high availability. It's a term commonly used to define a level of reliability for systems, indicating that the system is expected to be operational 99.999% of the time, translating to very minimal downtime.