Selection of initialization method for creating RAID

Keep Old data

This initialization method is suitable for deleting RAID by mistake. The premise is that after you delete it by mistake, no disk has been written or the TRIM function takes effect. There is no read or write operation for the disk, just for data recovery.

Quick init

This creation method is only recommended to users for performance testing. There is no read operation for the disk, only a small part of the write operation. The data written is very small, usually at the end of the disk, used to verify the organization of the RAID, such as the basic information of the RAID, the capacity of the RAID, and which member disks are,etc. This operation has no effect on the disk.

Foreground(recommend)

Foreground will write 0 to the disk. Create redundant RAID, it is recommended to use this method for initialization. 

Background

The background reads first and then writes. The source disk is read and written to the verification disk.

Verify and Rebuilding

Verify

Check whether the source disk data is consistent with the target disk data. Only read comparison, no write operation. Assuming that the data is damaged, verify is used to detect whether the RAID is broken.

Rebuilding

Read the source disk, then write to the target disk. Rebuilding is established after verify fails. Rebuilding operation will cause performance degradation, this is unavoidable.