Hitachi G800 Hardware Reference Manual page 72

Item
Control method
Battery backup
Backup duration
Data in the cache memory is preserved against power failures. If a power outage occurs,
data in cache memory is written to drives.
When the storage system enters Cache Backup mode, the amber WARNING LED goes on
to when the system starts. This warning indicates that the battery charge has dropped
significantly and the remaining battery capacity is not sufficient; the storage system will
continue operating with the Write Cache function disabled.
When the battery is charged, the warning indication disappears, and the storage system
continues the operation in the Write Cache function.
The warning indication disappears within six hours. Even when the warning is shown,
normal operation is assured in Write-Through. Read and write performance is lowered
because the Write Cache function is disabled.
If the storage system is not charged for more than six months, the battery can become
overcharged and sustain unrecoverable damage. To avoid this situation, charge the
battery more than 3 hours every six months.
Insulation performance
Item
Insulation withstand voltage
Insulation resistance
Appendix A: Mechanical specifications for VSP G800
Hitachi Virtual Storage Platform G800 Hardware Reference Guide
VSP G800 mechanical specifications
Specification
Note:
All 12 slots must be fully
■
installed with DIMMs.
Each DIMM is replaceable
■
when they fail.
The DIMM is not common
■
and cannot be used with
DKC DIMM.
Read LRU, Write after
Provided
Unrestricted (saving to a nonvolatile
memory)
Specification
AC 1,500 V (100 mA, 1 min)
DC 500 V, 10 M Ω or more
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