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Compaq HSZ80 Array Controller ACS Version 8.3 Configuration and CLI Reference Guide
Figure 3–5. Mirrorsets Maintain Two Copies of the Same Data
Considerations for Planning a Mirrorset
Keep these points in mind as you plan your mirrorsets:
■ A controller can support up to 30 storagesets, consisting of mirrorsets and
RAIDsets. Mirrorsets that are members of a stripeset count against this limitation
(see Table 3–1).
■ Data availability with a mirrorset is excellent but costly—you need twice as
many disk drives to satisfy a given capacity requirement. If availability is your
top priority, consider using redundant power supplies and dual-redundant
controllers.
■ You can configure up to 30 mirrorsets per controller or pair of dual-redundant
controllers. Each mirrorset contains a minimum of one member and a maximum
of six members.
■ A write-back cache module is required for mirrorsets, but write-back cache need
not be enabled for the mirrorset to function properly.
■ Both write-back cache modules must be the same size.
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CXO5511A
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Mirror drives contain
copy of data