Adding disks to Dell SAN – Grow RAID, virtual disks and OS volumes

Adding disks to a SAN can be a long process. In this case we added 12x 600GB SAS drives to a Dell PowerVault SAN. The SAN was configured with 3x RAID groups (RAID10, RAID1 and RAID5) which are split into 2 virtual disks per group.

The process to install the new disks and grow the RAID, virtual disks and volumes:

  1. If your SAN has hot swappable drives, you install the drives while the SAN is on.
  2. Log into the Dell storage manager
  3. Go to the Logical tab.
  4. Right click on the RAID group and select ‘Add free capacity (Physical disks)’.

5. Select which disks you would like to add to the pool.

6. You will notice that it adds the new disks as free capacity to the pool. Note that this  process can take very long – In this case 1 hour per 100GB. So it took 12 hours to add 2x 600GB to the pool. You can monitor the progress on the summary tab, ‘Operations in progress’.

7. After the process of adding the disks to the group is complete you need to add the available free space to the virtual disk within the group. This process can also take very long depending on if it needs to move other virtual disks on the SAN to be able to add the necessary space. The one virtual disk that I increased took 40 minutes for adding 300GB, the other took almost 6 hours as it had to move another virtual disk in order to be expanded.

8. Once you have added free space to a virtual disk, you can log into the OS that use the virtual disk and extend the windows volume.