External Cache Battery - Compaq StorageWorks HSZ80 Configuration And Cli Reference Manual

External Cache Battery

To preserve the write-back cache data in the event of a primary power failure, a cache
module must be connected to an ECB or a UPS.
Compaq supplies two versions of ECBs: a single-battery ECB for single controller
configurations, and a dual-battery ECB for dual-redundant controller configurations,
which is shown in Figure 1–9. When the batteries are fully charged, an ECB can
preserve 512 MB of cache memory for 24 hours. However, the battery capacity
depends upon the size of memory contained in the cache module, which are listed in
Table 1–10.
64 MB
128 MB
256 MB
512 MB
Table 1–10 ECB Capacity Based on Memory Size
Size DIMM Combinations
Two, 32 MB each
Four, 32 MB each
Two, 128 MB each
Four, 128 MB each
Compaq HSZ80 Array Controller ACS Version 8.3 Configuration and CLI Reference Guide
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Capacity
96 hours
48 hours
48 hours
24 hours