Hot-swapping with SCA
With SCA, it is possible to hot-plug devices. Unfortunately, this is not as simple as it should be, but it is both possible and safe.

Replace the RAID device, disk device, and host/channel/id/lun numbers with the appropriate values in the example below:

Dump the partition table from the drive, if it is still readable:

sfdisk -d /dev/sdb > partitions.sdb

Remove the drive to replace from the array:

raidhotremove /dev/md0 /dev/sdb1

Look up the Host, Channel, ID and Lun of the drive to replace, by looking in

/proc/scsi/scsi

Remove the drive from the bus:

echo `scsi remove-single-device 0 0 2 0` > /proc/scsi/scsi

Verify that the drive has been correctly removed, by looking in

/proc/scsi/scsi

Unplug the drive from your SCA bay, and insert a new drive

Add the new drive to the bus:

echo `scsi add-single-device 0 0 2 0` > /proc/scsi/scsi

(this should spin up the drive as well)

Re-partition the drive using the previously dumped partition table:

sfdisk /dev/sdb < partitions.sdb

Add the drive to your array:

raidhotadd /dev/md0 /dev/sdb2

The arguments to the `scsi remove-single-device` commands are: Host, Channel, Id and Lun. These numbers are found in the `/proc/scsi/scsi` file.