Hi, my name is Chris, and I’m a Global Support Engineer with Dell EMC Support. Today, I wanted to talk about hot spare hard drives. Now, a hot spare drive is just a drive in a special status whose only functional job is to wait for one of your RAID member drives to either fall offline, go into a foreign state, or otherwise exit an online status. Once that occurs, the hot spare drive will rebuild into your array, minimizing the amount of time that your RAID spends in a degraded or partially degraded state.
Now, the key there is that it is a special status, so we have to go in and assign it. Your server won’t automatically rebuild just any drive that’s in your server into the array. So, in order to do that, we’ll go ahead and boot to this screen here, which is the 'System Setup' screen. We get here by pressing F2 during POST. Once we’re here, we’ll click on 'Device Settings', and then once that loads up, we’ll go into our RAID controller. Today, I’ve got a NH730P adapter. From the main menu, we’ll simply come down to 'Physical Disk Management', and then we have our list of drives here.
You’ll notice that the first three drives here are all in an 'Online' status; they’re part of my RAID 5. The last one here is 'Ready'. This is the one we’re going to assign as a global hot spare. So, we’ll select it and then 'Operation'. To select Operation here, these are all the different options that we have. Toward the very bottom here, we have 'Assign Global Hot Spare' and Assign Dedicated Hot Spare'. For our purposes, we’ve only got the one RAID array. It’s the same size capacity drive as all the other drives, so we’re just going to assign a global hot spare.
The primary difference between these two options is that if you assign a dedicated hot spare, you have to take the extra step of selecting which virtual disks that hot spare is assigned to, and it will only rebuild into one of those virtual disks that you select for it. A global hot spare will attempt to rebuild into any array that it is a valid component to rebuild into. So, we’ll go ahead and select this and then click Go'. That’s it. We see this screen here that says it’s successful. We click 'OK', and it takes us back to the drive page. Then we can just click Back. Notice here that it still says 'Ready'.
We actually have to go back to the main menu and then click 'Physical Disk Management' again to get it to properly refresh. But now it shows that it is a hot spare, and this is all the configuration that we need to do. Now, if one of these drives here falls offline, this drive will automatically kick in and begin a rebuild, and it’ll put the array back into an optimal state. Then we’ll have plenty of time for our admin to contact support and get the drive replaced or swap it with a shelf spare or whatever our remediation strategy for a failed drive is.
Okay, thank you very much. Bye.