Failed to add SSD cache disk to storage UI. Error:failed to mkfs Device or resource busy

[nexus]

Problem description:
Failed to add SSD cache disk to storage UI. Error:failed to mkfs Device or resource busy

Problem analysis:

1. df -hT to check if the disk is mounted
2. There may be dirty data in the cache disk
3. The disk may have been RAIDed

Problem handling process:

1. Use the dd command to clear the cache disk (sdk) data, and pay attention to setting the bs and count data according to the cache disk size.

dd if=/dev/zero of=/dev/sdk bs=1M count=1000

Where: sdX is the disk symbol of the system to be installed, use fdisk to view,
To format the disk, write 1000 consecutive blocks of 1M binary zeros to the target disk.

2. The disk may have been RAIDed. After entering the raid interface for formatting, re-add the cache disk