Separation of software business and hardware platform
A very important requirement for data center software is High Availability (HA). For example, the high availability of backend services is achieved through a load balancer, and the load balancer itself also achieves its own high availability through a cluster mechanism. The underlying VM achieves high availability through live migration, and the container achieves high availability by automatically pulling up new instances in the new environment.
If we pay attention to the underlying software and hardware, we will find that the actual running software (regardless of the virtualization part, virtualization is actually a virtualization mechanism between software and hardware, through the cooperation of software and hardware) and hardware actually is completely disengaged:
Software entities can run on different hardware platforms and can be migrated in real time. The upper-layer software thinks that the software entities are always highly available and cannot feel the changes of the underlying hardware (hardware may fail disks, crash or update servers, etc.).
A complete single hardware platform can be flexibly divided into many virtual hardware platforms through virtualization, which can support the operation of different software entities.