Infortrend RAID Controller Manual

E-2
earlier firmware revisions. There is no problem with firmware
upgrade.
Logical arrays created by revision 3.21 will be stated as "invalid"
by controllers installed with earlier revisions.
3. If incompatibility occurs, users will not be able to access the
original array unless he switches back to revision 3.21.
4. Backward Compatibility:
Users may create logical drives that can accessed by both lines of
firmware in the first place. To create logical drives that are
"backward compatible," select a compatible reserved space
(64KB) when creating a logical drive. The process is shown in
the diagram below:
Using Old Drives:
If the controller has recently been upgraded to firmware version
3.21 and drives had been used in a logical drive, controller will
ask for a change in the reserved space. Every physical drive that
had been included in the logical drive will have a small sector
formatted and its status will be displayed as a "FRMT
(formatted) DRV."
You will be prompted with the similar options using the Quick
Install function. The selection box will not appear when all
drives are new or that reserved space has been removed from
drives.
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