Hitachi g800 - Page 72

Item Specification
Note:
■
All 12 slots must be fully
installed with DIMMs.
■
Each DIMM is r
eplaceable
when they fail.
■
The DIMM is not common
and cannot be used with
DKC DIMM.
Control method Read LRU, Write after
Battery backup Provided
Backup duration Unrestricted (saving to a nonvolatile
memory)
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 stor
age 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
signicantly and the remaining battery capacity is not sucient; 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 Specification
Insulation withstand voltage AC 1,500 V (100 mA, 1 min)
Insulation resistance DC 500 V, 10 M Ω or more
VSP G800 mechanical specications
Appendix A: Mechanical specications for
VSP G800
Hitachi Virtual Storage Platform G800 Hardware Reference Guide 72