You want to DOD wipe the drives with disk sanitization if you are sending them off to asset disposal.
install the disk sanitization license and then run this command
disk sanitize start-c7 (enter disk list here)
the number 7 is the number of passes..
After You Finish
You can monitor the status of the sanitization process by using the /etc/sanitized_disks and /etc/sanitization.log files:
Status for the sanitization process is written to the /etc/sanitization.log file every 15 minutes.
The /etc/sanitized_disks file contains the serial numbers of all drives that have been successfully sanitized. For every invocation of the disk sanitize start command, the serial numbers of the newly sanitized disks are appended to the file.
This process could take a week or more depending on number of passes. Do not turn off the system while you are doing this.
once you sanitize, you will never get the data back ever, so make sure you do this on the right disks.
Good idea to sanitize the disks as mentioned in the other post to ensure no one that gains physical access to the disks can reconstruct the data. Once that is done, the proper way to shutdown the system is to connect to the command line and type:
priv set advanced
halt -c factory (this sets the system back to factory settings before shutting down the operating system)
Then power off the storage controller and then the disk shelves.