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Manage hard disk drives
About hard disk drives
Images from cameras will be recorded on the hard disk drive(s) in the recorder.
This recorder manages the hard disk drives by dividing them virtually into the following recording areas.
• Normal recording area:
Recording area used when an event does not occur (Manual recording, schedule recording)
• Event recording area:
Recording area used when an event occurs (Post-event recording, emergency recording).
• Pre-event recording area:
Recording area used to record images before an event occurs
It is possible to assign only one recording area to a hard disk drive.
The settings of each recording area can be configured on the disk configuration page. (
☞
Page 127)
Remaining capacities of each recording area can be checked on the disk configuration page or the "Maintenance" page - the
"Disk information" tab. (
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Page 119)
About the RAID 5/RAID 6 mode
The RAID 5/RAID 6 mode becomes available when optional RAID boards (WJ-HDB601E) are installed in the recorder and exten-
sion units.
When the RAID5/RAID6 mode is applied, 3 or more hard disk drives are regarded logically as a single drive. Even if a trouble
occurs in one of the hard disk drives, the data on the faulty hard disk drives can be recovered based on the error correction data
automatically recorded on the other drives.
The RAID 5 mode has an error correction data that recovers data when a single hard disk drive becomes faulty. The RAID 6
mode has two error correction data that recovers data from other disk drives when two drives become faulty at the same time.
• Logical disk capacity in the RAID 5 mode
Logical disk capacity = Capacity of the smallest hard disk drive among the unit x (Total number of the hard disk drives in the
unit - 1)
• Logical disk capacity in the RAID 6 mode
Logical disk capacity = Capacity of the smallest hard disk drive among the unit x (Total number of the hard disk drives in the
unit - 2)
* Depending on the models of hard disk drives installed in the recorder, the capacity may be a few percent smaller.
Important:
• To enable the RAID 5 mode, it is necessary to install 3 or more hard disk drives in the recorder. To enable the RAID 6 mode, it
is necessary to install 4 or more hard disk drives in the recorder.
• When an optional RAID board (WJ-HDB601E) is not installed in the recorder, it is impossible to enable the RAID 5/RAID 6
mode using the recorder alone.
• The RAID 5/RAID 6 mode is determined using the [RAID] switch behind the front panel (operating section) of the recorder. (
☞
Page 20)
• Refer to the operating instructions of extension units for further information about how to determine the RAID 5/RAID 6
mode.
Determine the operation mode
The RAID 5/RAID 6 mode is determined using the [RAID] switch (
☞
page 20) behind the front panel (operating section) of the
recorder.
Refer to page 54 for how to determine the operation mode.
