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The capacity of the Hot Fix Drive has to be larger or equal than the capacity of the compo-
nents of the Array Drive (Example: The Logical Drives of the Array Drive have 4.2GB capac-
ity, thus the capacity of the Hot Fix Drive has to be 4.2GB or larger).
The spindle motor of the Hot Fix Drive is normally (i.e., when the Hot Fix Drive is not
needed) stopped. Thus, it may take a few seconds until you get a response, if you click on
that drive.
Some general notes on Hot Fix Drives.
One of the reasons that have led you to choose RAID disk arrays definitely lies with the re-
dundancy, that is, the data security you still preserve even in the event of disk failure, thus
resting assured against loss of data and time. Hot Fix Drives are possible with all RAID 1, 4,
5 and 10 disk arrays. In order to assist the following considerations, we define the term time
without redundancy, TWR. Set apart the time needed to set up the disk array (state build),
the time without redundancy should be kept as short as possible. Let us assume that one
of the hard disks of the RAID 5 disk array we set up with example 1 fails. The disk array is
without redundancy. TWR starts to run. Any superfluous prolongation of the TWR (because
you have to get a replacement drive, or because you did not realize the failure immediately
since you didn't hear the ICP Controller's alarm signal, or because nobody checked the file
server) increases the risk of data loss which will occur if a second drive should fail. There-
fore, new redundancy should be created as soon as possible and in an entirely automated
manner. Integrating a Hot Fix Drive as an immediately available and auto-replacing drive is
the only way to keep the TWR as short as possible. Only a Hot Fix drive can ensure optimal
disk array security and constant data availability. Of course a Hot Fix Drive is not compul-
sory. If you control the disk array at regular intervals and immediately replace a defective
drive (by shutting down the system or hot-plugging), you can do without a Hot Fix Drive.
K.5.12 Remove a Hot Fix Drive
Click the right mouse button on the Array Drive icon.
This option opens a box showing available Hot Fix Drives. Here you can select the Hot Fix
Drive you want to remove from the Array Drive and then confirm your selection. You can
remove any Pool Hot Fix Drives or the Private Hot Fix Drive of the selected Array Drive.
K.5.13 Hot Fix Pool Access
Click the right mouse button on the Array Drive icon.
Here you can enable or disable the access of an Array Drive to the pool hot fix of Hot Fix
Drives. If the access is enabled this means that if a member of an Array Drive fails, a drive
can be taken from the Hot Fix Pool and build automatically into the Array Drive. To be able
to activate this feature, there must be suitable Logical Drives in the Hot Fix Pool. You can
add drives to the Hot Fix Pool with the function Add Hot Fix Drives. By doing so, the Hot Fix
Pool access for this specific Array Drive is activated automatically. For all other Arrays Drive
you have to activate the access manually.
K.5.14 Add a RAID 1 Component (Mirror a Drive)
Click the right mouse button on the Logical Drive icon.
In certain "emergency" cases this is a very powerful and helpful option. This function allows
you to add to a Logical Drive which is member of an Array Drive, another Logical Drive as a
mirror drive (RAID 1).
Example: You have configured an Array Drive with 4 Logical Drives. One Logical Drive has
failed and the Array Drive went into the fail state. Another failure would cause data loss.
Unfortunately, you find another Logical Drive, which is shortly before failing (e.g., you hear
a strange noise from it, or it's grown defect counter explodes). If you now initiate a hot plug
it is very likely that this critical Logical Drive will also fail. This would result in a disaster.
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