Fault Tolerant Operation
everRun software provides two user-defined availability levels for VMs: High Availability (HA) and Fault Tolerant (FT). In FT operation, an application continues to run without downtime during a fault. Use FT for applications that need the highest levels of availability.
You select a VM’s availability level when you create or import the VM by using the everRun Availability Console.
In FT operation, the everRun software transparently protects an application by creating a redundant environment for a VM running across two physical machines (PMs). With an identical instance of the selected VM on a second host, the everRun software provides FT-class protection of the VM.
When enabled, FT operation transparently protects a VM from all faults, with no downtime, and FT operation:
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Eliminates downtime due to any CPU, memory, I/O, or other physical machine (PM) failure.
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Handles failures without IT intervention.
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Ensures no data loss.
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Provides continuous, active validation of all components.
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Assures complete redundancy and recovery at all times.