How low spare warnings can help you manage your spare drives

By default, Data ONTAP issues warnings to the console and logs if you have fewer than one hot spare drive that matches the attributes of each drive in your storage system. You can change the threshold value for these warning messages to ensure that your system adheres to best practices.

To make sure that you always have two hot spares for every drive (a best practice), you can set the min_spare_count RAID option to 2.

Setting the min_spare_count RAID option to 0 disables low spare warnings. You might want to do this if you do not have enough drives to provide hot spares (for example, if your storage system does not support external disk shelves). You can disable the warnings only if the following requirements are met:

Your system has 16 or fewer drives.
You have no RAID groups that use RAID4.
Note: You cannot create aggregates that use RAID4 protection while the raid.min_spare_count option is set to 0. If either of these requirements is no longer met after this option has been set to 0, the option is automatically set back to 1.