Rackable Systems OmniStor 4700S Series, User Manual

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Chapter 2 - Operating Mode and Topologies
How Available are Clusters?
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How Available are Clusters?
This table outlines the maximum availability per downtime in the different architectures:
Application of Availability
The OmniStor 4700S Series RAID Storage Systems implementation of availability within
its supported topologies are as follows:
Architecture
Maximum
Availability
Downtime per
Failure
Downtime per Year
(in minutes)
Continuous Processing 100.00% None 0
Fault-Tolerant 99.9999% Cycles 0.5 - 5
Clusters 99.9 - 99.999% Seconds to
minutes 5 - 500
High Availability 99.9% Minutes 500 - 10,000 (disk
mirroring)
Stand Alone System 99.5% Hours 2,600 - 10, 000
(without disk
mirroring)
Architecture Corresponding Topology
Continuous Processing Not Available
Fault-Tolerant Not Available
Cluster Simplex Cluster
High Availability Simplex Dual Host
Stand Alone System Simplex Single Host