Configure Global Spare Hard Drive using HP ACU

Most of the HP Servers are shipped with HP Smart Array Storage controllers. These controllers will allow you to create and manage hardware RAID on your server. You can create, delete, migrate, expand, extend arrays using the HP Array configuration Utility (HP ACU). HP ACU also helps us to assign spare hard drive for an array.
Today, we will discuss how to assign a “Global Spare” hard drive using HP Array Configuration Utility. Global Spare hard drive is also called as Shared Spare. As the name implies, Global Spare hard drive is the hard drive which is shared across different Arrays. When we assign same spare drive to multiple arrays, it is called Global Spare.

We have already discussed about assigning dedicated Spare hard drives to an Array. If you haven’t read, please refer the below provided article to find how to assign dedicated Spare HDD to an array using ACU.

Guide: Configure Online Spare HDD using HP ACU
Please note that Array Configuration Utility will ensure that SAS hard drives can only be assigned as spare for SAS array and likewise, SATA hard drives can only be assigned to an Array which has SATA arrays. Keep in mind that an array can have several online spares, and any of these spare hard drive can be shared by several arrays. When a physical hard drive fails in an array, the Global Spare HDD will get activated and will rebuild the failed Array. In short, your data and array will be more secure when you have a Spare HDD assigned to an array.
Here, I am using HP P410i Smart Array Controller with ACU 8.6. We have 5 Unassigned Physical HDDs installed on this Server. HDDs are installed in Bay 1, 2, 3, 4 and bay 5. I will create the first array (RAID1) using the HDDs installed in Bay 1 and 2. Later, I will create another Array (RAID1) using the HDDs installed in bay 3 and 4. Once we are done, we will go ahead assign the HDD in bay 5 as a global spare (Shared spare) for both the arrays we have created.

Steps we need to follow:

Step 1: Create two Arrays and Logical Drives on your Server.
Step 2: Assign one free HDD as Global Spare (Shared Spare) to both Arrays.
Step 1: Create two Arrays and Logical Drives on your Server
If Windows OS is installed on your Server, then you can find HP Array Configuration Utility listed under Programs –> HP System Tools –> HP Array Configuration Utility. Please visit our Guide about HP Array configuration utility to understand how to launch ACU on your Server.
Guide: Configure RAID using HP ACU on your HP Server
1. Open HP Array Configuration Utility on your Server.


Here we have 5 Unassigned Physical HDDs available. HDDs are installed in Bay 1, 2, 3, 4 and Bay 5. We will use first 4 HDDs (2+2) to create two RAID 1 Array on this server. Later, we will assign remaining one HDD (bay 5) to both of these RAID 1 array as Global spare.
2. Change the View to “Physical View” (Note: This is for better understanding)

3. Select Unassigned Drives, on the left pane of window, click on Create Array.

4. Select two HDDs and Click on OK button (We selected HDDs in Bay 1 and 2)

5. Now we have created a new Array called SAS Array A (Shown below).
6. Now create a new logical drive, click on Create Logical Drive.

7. Select RAID 1 as Fault tolerance and click on Save button.

8. Now we have successfully created Logical drive 1 under SAS Array A.
9. Let us create one more Array using another 2 HDDs installed on the server
10. Click on Unassigned Drives and click Create Array

11. Select 2 HDDs and Click on OK button (We selected HDDs in Bay 3 and 4)

12. Click on OK. Now a new array called SAS Array B will be created.
13. Let us create a New Logical Drive under SAS Array B.
14. Select SAS Array B and click on Create Logical Drive.

15. Select RAID 1 as Fault Tolerance and Click Save

16. Now the Logical drive 2 is created under SAS Array B.


As shown in above provided image, we have created two RAID Array named SAS Array A and SAS Array B. We also have Logical drive 1 and Logical drive 2 created under Array A and Array B . Now we will assign the remaining free HDD in Bay 5 to both SAS Array A and SAS Array B.  Remember, we can assign Spare HDDs only to Array not to Logical drives
Step 2: Assign one free HDD as Global Spare (Shared Spare) to both Arrays
17. Now assign the Spare HDD (bay 5) to both SAS Array A and B.
18. Select SAS Array A and click on Spare Management

19. Select the unassigned HDD which is installed in bay 5 as the spare.

20. Now the bay 5 HDD is assigned as the dedicated Spare of SAS Array A (Shown below)

21. Now we will assign the same Bay 5 HDD as a spare to SAS Array B (Shared Spare).
22. Select SAS Array B and click on Spare Management

23. Now select the same Bay 5 HDD as spare for SAS Array B. Click on Save

24. Now the Bay 5 HDD will act as the spare for both SAS Array A and B.

25. Congrats, now the same HDD (Bay 5 HDD) is shared and its called as Global Spare

---

Note that we can only assign a spare hard drive to an Array. We do not have a provision to assign a spare hard drive to a logical drive. When a physical hard drive fails in an array, the spare hard drive will kick-in and will rebuild all the logical drives in that array.