Dell Storage Manager 2020 R1 Administrator's Guide

Modify Tier Redundancy

Modify tier redundancy to change the redundancy level for each tier in a Storage Type. After modifying tier redundancy, a RAID rebalance is required to move data to the new RAID levels.

1. If the Dell Storage Manager Client is connected to a Data Collector, select a Storage Center from the Storage view.
2. Click the Storage tab.
3. In the Storage tab navigation pane, click Storage Types, then click the Storage Types subtab.
4. Right-click the Storage Type to modify and select Modify Tier Redundancy.
   The Modify Tier Redundancy dialog box opens
5. Modify the redundancy for each tier as needed.
   • Redundant: Protects against the loss of any one drive (if single redundant) or any two drives (if dual redundant).
   • Non-Redundant: Uses RAID 0 in all classes, in all tiers. Data is striped but provides no redundancy. If one drive fails, all data is lost.
     NOTE:Non-Redundant is not recommended because data is not protected against a drive failure. Do not use non-redundant storage for a volume unless the data has been backed up elsewhere.
6. For Redundant Storage Types, you must select a redundancy level for each tier unless the drive type or size requires a specific redundancy level
   • Single Redundant: Single-redundant tiers can contain any of the following types of RAID storage:
     • RAID 10 (each drive is mirrored)
     • RAID 5-5 (striped across 5 drives)
     • RAID 5-9 (striped across 9 drives)

   • Dual redundant: Dual redundant is the recommended redundancy level for all tiers. It is enforced for 3 TB HDDs and higher and for 18 TB SSDs and higher. Dual-redundant tiers can contain any of the following types of RAID storage:
     • RAID 10 Dual-Mirror (data is written simultaneously to three separate drives)
     • RAID 6-6 (4 data segments, 2 parity segments for each stripe)
     • RAID 6-10 (8 data segments, 2 parity segments for each stripe.)
7. Drive Addition is selected by default. Leave this option selected.
8. Click OK.
   A RAID rebalance starts.