Removing disks

Reasons to remove disks

You remove a disk for the following reasons:

You want to replace the disk because
- It is a failed disk. You cannot use this disk again.
- It is a data disk that is producing excessive error messages, and is likely to fail. You cannot use this disk again.
- It is an old disk with low capacity or slow RPMs and you are upgrading your storage system.
You want to reuse the disk. It is a hot spare disk in good working condition, but you want to use it elsewhere.
Note
You cannot reduce the number of disks in an aggregate by removing data disks. The only way to reduce the number of data disks in an aggregate is to copy the data and transfer it to a new file system that has fewer data disks.

Removing a failed disk

To remove a failed disk, complete the following steps.

Step	Action
1	Find the disk ID of the failed disk by entering the following command: aggr status -f Result The ID of the failed disk is shown next to the word failed. The location of the disk is shown to the right of the disk ID, in the column HA SHELF BAY.
2	If the disk is a...	Then...
	Fibre Channel disk or in a Fibre Channel-attached shelf	Go to Step 3.
	SCSI disk or in a SCSI-attached shelf	Enter the following command and go to Step 3: disk swap
3	Remove the disk from the disk shelf according to the disk shelf manufacturer's instructions.

Removing a hot spare disk

To remove a hot spare disk, complete the following steps.

Step	Action
1	Find the disk IDs of hot spare disks by entering the following command: aggr status -s Result The names of the hot spare disks appear next to the word spare. The locations of the disks are shown to the right of the disk name.
2	Enter the following command to spin down the disk: disk remove disk_name disk_name is the name of the disk you want to remove (from the output of Step 1).
3	If the disk is...	Then...
	A Fibre Channel disk or in a Fibre Channel-attached shelf	Go to Step 4.
	A SCSI disk or in a SCSI-attached shelf	Enter the following command, and go to Step 4: disk swap
4	Wait for the disk to stop spinning. See the hardware guide for your disk shelf model for information about how to tell when a disk stops spinning.
5	Remove the disk from the disk shelf, following the instructions in the hardware guide for your disk shelf model. Result: When replacing FC disks, there is no service interruption. When replacing SCSI and ATA disks, file service resumes 15 seconds after you remove the disk.

Removing a data disk

To remove a data disk, complete the following steps.

Step	Action
1	Find the disk name in the log messages that report disk errors by looking at the numbers that follow the word Disk.
2	Enter the following command: aggr status -r
3	Look at the Device column of the output of the `sysconfig -r` command. It shows the disk ID of each disk. The location of the disk appears to the right of the disk ID, in the column HA SHELF BAY.
4	Enter the following command to fail the disk: disk fail [-i] disk_name `-i` specifies to fail the disk immediately. disk_name is the disk name from the output in Step 1.
	If you...	Then...
	Do not specify the `-i` option	Data ONTAP pre-fails the specified disk and attempts to create a replacement disk by copying the contents of the pre-failed disk to a spare disk. This copy might take several hours, depending on the size of the disk and the load on the storage system. Attention You must wait for the disk copy to complete before going to the next step. If the copy operation is successful, then the pre-failed disk is failed and the new replacement disk takes its place.
	Specify the `-i` option or if the disk copy operation fails	The pre-failed disk fails and the storage system operates in degraded mode until the RAID system reconstructs a replacement disk.
5	If the disk is...	Then...
	A Fibre Channel disk or in a Fibre Channel-attached shelf	Go to Step 6.
	A SCSI disk or in a SCSI-attached shelf	Enter the following command, then go to Step 6: disk swap
6	Remove the failed disk from the disk shelf, following the instructions in the hardware guide for your disk shelf model. Result: File service resumes 15 seconds after you remove the disk.

Cancelling a disk swap command

To cancel the swap operation and continue service, complete the following step.

Step	Action
1	Enter the following command: disk unswap