Chapter 5: Subsystem Maintenance and Upgrading
Feature
64-bit LBA Support (>2TB)
Number of LDs
Number of LVs
Number of Partitions per LD
Number of LUNs per Channel lD
Number of LUNs
Optimization Mode
Caching Mode (Default)
Stripe size(
Sequential I/Os-RAID 5)
Optimization for
Auto-assign Global Spare
Max. LD capacity (Optimization for Sequential I/Os)
No. of Media Scan Task Schedules
Max. No. of members per DIMM size (RAID5)
<1GB DIMM
Yes
16 (Max.)
8 (Max.)
128 (Max.)
Sequential I/O
Write-Back
128KB
Disable
64TB (Max.)
16 (Max.)
128 drives max. / 512MB
De f a u lt Va lu e
Yes
> 1GB DIMM
=
32 (Max.)
16 (Max.)
16 (Max.)
64 (Max.)
8 (32 Max.)
1024 (Max.)
8 (32 Max.)
This parameter threshold, however, can cause problems if users
upgrade DIMM modules to a larger size, especially when combining
two RAID controllers, without knowing their NVRAM defaults. The fault
can also occur when replacing a faulty controller in a redundant-
controller configuration.
Fault Scenarios:
․
Field-side Upgrade:
-- Customers upgrade controller DIMM modules, e.g., from
512MB to 1GB.
-- Combine controllers into a redundant configuration. One
retains the “512MB” defaults, while the other the “
≥
1GB”
defaults.
․
Replacing a Failed Controller:
-- Branch office acquires a replacement controller and
upgrades its memory to the size of surviving controller.
-- Though with the same memory size, the replacement still
retains the incongruous defaults.
The RAID system will report a “Redundant Controller Failure”
event, and the controllers will not work coherently.
Remedy:
-
Restore firmware defaults
after installing/changing the DIMM
module. You can either use the Restore Default button or the
LCD keypad panel.
- The easiest way to check the type of firmware defaults is
through the “View and Edit Logical Drives” menu.
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