Rescanning for Changes in State
When using the bcadm program, the disk information that displays when you run a query command is always current. In the RAIDConsole appli- cation, however, the information displayed in the Disk List area is the state of the disks when they were last scanned. If you have not performed a rescan, the information being displayed is the state of the disks at boot time.
Every time you connect or disconnect a disk while online, a message ask- ing if you want to perform a rescan (of all SATA channels) appears. If you choose Yes, the information in both the Array List and the Disk List is updated. However, this view may show arrays as being in a CRITICAL or OFFLINE state if not all disks have been installed or removed.
Although it is highly recommend that you shut down the system before you add or remove disks, you may also be able to add or remove disks while online if your system supports that feature. Because of this feature, RAIDConsole does not automatically perform a rescan when it detects that a disk has been added or removed. For example, if you want to hot- swap a RAID5 set with six disks into a new system, do not perform a res- can until all six disks have been connected. Otherwise, any arrays associ- ated with the disks that are not yet connected change state to either CRITICAL or OFFLINE. If the state of your RAID5 set changes to OFFLINE, you will lose your data. This feature can also result in the state of a disk being reported differently in the Array View and the Disk List. A disk within an array can have a state of FAILED in the Array tree view while at the same time it can show a state of NORMAL in the Disk List.
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