Several systems on one machine.
WHAT IT IS
Running several independent systems on one physical server.
WHAT THAT ACHIEVES
Better use of hardware Isolation between workloads Faster provisioning Easier movement between machines
WHY IT MATTERS FOR FACILITIES
Fewer physical machines for the same work, consuming less power, space and cooling.
WHAT IT REQUIRES
Sufficient memory, primarily Storage fast enough for several systems at once
WHAT LIMITS HOW MANY
Memory, usually. It cannot be shared as processors can.
WHAT IT INTRODUCES
A dependency on the host: its failure affects everything on it.
WHAT THAT REQUIRES
Several hosts, and the ability to move workloads between them.
WHAT TO AVOID
Concentrating everything critical on one host Overcommitting resources beyond what is available
WHAT TO MONITOR
Resource use per host, and per workload.
WHAT TO PLAN
Capacity to lose a host and continue.
WHAT THIS IS UNDERNEATH
Most hosting, including shared hosting and virtual servers.
