Product specifications

Infortrend
9-2
Select “View and Edit Peripheral Devices” on the Main Menu and
press [ENTER]. Choose “Set Peripheral Device Entry”, press
[ENTER], then select “Event Trigger Operations” by pressing
[ENTER]. The event trigger menu displays.
The Operations
To reduce the chance of data loss, the controller/subsystem
automatically commences the following actions to prevent loss of
data:
1). Switches its caching mode from write-back to write-through
2). Flushes all cached data
The Trigger
The mode switching and cache flush operations can be triggered by
the detection of the following conditions:
1. BBU low or failed:
If battery fails or is under-charge, the unfinished writes
cannot be supported if power outage occurs.
2. UPS AC power loss:
Even with the buffer provided by the UPS, if the mains
power fails, cached data should be immediately
distributed to hard drives.
3. Power supply failure
4. Fan failure
5. Temperature exceeds threshold
If critical conditions occur, such as the enclosure
component failure, chance of system downtime will
increase and it is best to temporarily disable write-back
caching.
When enabled, each of the above conditions forces the
controller/subsystem to adopt the write-through caching mode.
When the fault condition is corrected, the controller/subsystem
automatically restores the previous caching mode.
Figure 6 - 2: Controller Write-Through Alert
Note that the temperature thresholds refer to those set for both
sensors on the RAID controller boards and those placed within the
subsystem enclosure. In terms of the controller temperature, board
1 refers to the main circuit board and board 2 refers to the second-