High Availability, Scalability, Elasticity, Agility - Moumbeh/AZ-900-Cheat-Sheet GitHub Wiki

Cloud Computing Service delivery model over the internet (cloud). This includes, but is not limited to

• compute power meaning servers such as Windows, Linux, hosting environments, etc.

• storage like files and/or databases

• networking in Azure, but also outside when connecting to your company network

• Analytics services for visualisation and telemetry data

Key concepts

• Scalability is the ability to scale, so allocate and deallocate resources at any time

• Elasticity is the ability to scale dynamically

• Agility is the ability to react fast (scale quickly)

• Fault tolerance is the ability to maintain system uptime while physical and service component failures happen

• Disaster recovery is the process and design principle which allows a system to recover from natural or human-induced disasters

• High availability is the agreed-upon level of operational uptime for the system. It is a simple calculation of system uptime versus the system's lifetime.

availability = uptime/(uptime + downtime)

References https://learn.microsoft.com/en-us/azure/reliability/concept-business-continuity-high-availability-disaster-recovery https://en.wikipedia.org/wiki/Cloud_computing#Characteristics