Skip to main content

FAQs

Frequently asked questions...

  • What is redundancy check?
    A redundancy check determines whether the data on a volume in a pool or volume group is consistent. Redundancy data is used to quickly reconstruct information on a replacement drive if one of the drives in the pool or volume group fails.
  • What is preservation capacity?
    Preservation capacity is the amount of capacity (number of drives) that is reserved in a pool to support potential drive failures.
  • What RAID level is best for my application?
    To maximize the performance of a volume group, you must select the appropriate RAID level. You can determine the appropriate RAID level by knowing the read and write percentages for the applications that are accessing the volume group. Use the Performance page to obtain these percentages.
  • Why are some drives not showing up?
    In the Add Capacity dialog, not all drives are available for adding capacity to an existing pool or volume group.
  • Why can't I increase my preservation capacity?
    If you have created volumes on all available usable capacity, you might not be able to increase preservation capacity.
  • What is Data Assurance?
    Data Assurance (DA) implements the T10 Protection Information (PI) standard, which increases data integrity by checking for and correcting errors that might occur as data is transferred along the I/O path.
  • What is FDE/FIPS security?
    FDE/FIPS security refers to secure-capable drives that encrypt data during writes and decrypt data during reads using a unique encryption key. These secure-capable drives prevent unauthorized access to the data on a drive that is physically removed from the storage array.
  • What is secure-capable (Drive Security)?
    Drive Security is a feature that prevents unauthorized access to data on secure-enabled drives when removed from the storage array. These drives can be either Full Disk Encryption (FDE) drives or Federal Information Processing Standard (FIPS) drives.
  • How do I view and interpret all SSD Cache statistics?
    You can view nominal statistics and detailed statistics for SSD Cache. Nominal statistics are a subset of the detailed statistics. The detailed statistics can be viewed only when you export all SSD statistics to a .csv file. As you review and interpret the statistics, keep in mind that some interpretations are derived by looking at a combination of statistics.
  • What is shelf loss protection and drawer loss protection?
    Shelf loss protection and drawer loss protection are attributes of pools and volume groups that allow you to maintain data access in the event of a single shelf or drawer failure.
  • How do I maintain shelf/drawer loss protection?
    To maintain shelf/drawer loss protection for a pool or volume group, use the criteria specified in the following table.
  • What is the difference between internal security key and external security key management?
    When you implement the Drive Security feature, you can use an internal security key or an external security key to lock down data when a secure-enabled drive is removed from the storage array.
  • What do I need to know before creating a security key?
    A security key is shared by controllers and secure-enabled drives within a storage array. If a secure-enabled drive is removed from the storage array, the security key protects the data from unauthorized access.
  • Why do I need to define a pass phrase?
    The pass phrase is used to encrypt and decrypt the security key file stored on the local management client. Without the pass phrase, the security key cannot be decrypted and used to unlock data from a secure-enabled drive if it is re-installed in another storage array.