Based on the specified capacity of a LogicalVolume, number of LogicalVolumes and RAID level, the automatic LogicalVolume configuration creation (hereafter referred to as the automatic configuration function) automatically creates LogicalVolumes and assigns them to a RAIDGroup. It is also possible to specify automatic creation of a RAIDGroup to which LogicalVolumes should be assigned. Using this function thus makes it possible to easily configure a RAIDGroup and LogicalVolumes with excellent serviceability and availability.
The automatic configuration function creates and assigns LogicalVolumes as follows:
To secure sufficient availability, the automatic configuration function checks the hot spare capacity prior to LogicalVolume assignment. If a required hot spare disk does not exist or the capacity is too small, the function automatically configures a hot spare disk.
LogicalVolumes with larger capacities are preferentially assigned to a RAIDGroup. By preferentially allocating LogicalVolumes with larger capacities, a RAIDGroup can be used effectively and efficiently.
When two or more free spaces exist in a RAIDGroup, LogicalVolumes are assigned preferentially beginning from an area with smaller free space. Doing so enables the effective and efficient use of a RAIDGroup.
A RAIDGroup is allocated according to LogicalVolume assignment as shown below. The RAIDGroup to be used can also be selected from a list of existing RAIDGroups.
Distribution to individual RAIDGroups
A RAIDGroup with the smallest allocation to LogicalVolumes is allocated preferentially.
Distributing LogicalVolumes to RAIDGroups can distribute loads. If two or more RAIDGroups have the same size of LogicalVolume allocation, the one with the smallest RAIDGroup number is allocated preferentially.
Order of RAIDGroup numbers
RAIDGroups with smaller numbers are allocated preferentially.
The automatic configuration function configures a RAIDGroup by selecting disks evenly from individual groups to secure availability.
