Dell EMC H745P MX - Disk and Data Integrity Problems

CAUTION: The physical disk goes to Ready state when you clear the foreign conguration.
If you insert a physical disk that was previously a member of a virtual disk in the system, and that disk’s previous
location has been taken by a replacement disk through a rebuild, you must manually remove the foreign
conguration ag of the newly inserted disk.
Degraded state of virtual disks
A redundant virtual disk is in a degraded state when one or more physical disks have failed or are inaccessible. For example, if a RAID 1
virtual disk consists of two physical disks and one of them fails or become inaccessible, the virtual disk become degraded.
To recover a virtual disk from a degraded state, you must replace the failed physical disk and rebuild it. Once the rebuilding process is
complete, the virtual disk state changes from degraded to optimal.
Memory errors
Memory errors can corrupt cached data, so the controllers are designed to detect and attempt to recover from the memory errors. Single-
bit memory errors can be handled by the controller and do not disrupt normal operation. A notication is sent if the number of single-bit
errors exceeds a threshold value.
Multi-bit errors are more serious as they result in corrupted data and data loss. The following are the actions that occur in the case of multi-
bit errors:
• If a multi-bit error occurs while accessing data in the cache when the controller is started with dirty cache, the controller discards the
cache contents. The controller generates a warning message to the system console to indicate that the cache was discarded and
generates an event.
• If a multi-bit error occurs at run-time either in code/data or in the cache, the controller stops.
• The controller logs an event to the controller’s internal event log and a message during POST is displayed indicating a multi-bit error has
occurred.
NOTE
: In case of a multi-bit error, contact Dell Technical Support.
Preserved Cache State
The controller preserves the dirty cache from a virtual disk if the virtual disk goes oine or is deleted because of missing physical disks.
This preserved dirty cache is called pinned cache and is preserved until you import the virtual disk or discard the cache.
1 Import the virtual disk—Power o the system, re-insert the virtual disk and restore the system power. Use the HII Conguration
Utility to import the foreign conguration.
2 Discard the preserved cache—See Clearing the cache memory.
Security key errors
Secured foreign import errors
A foreign conguration is a RAID conguration that already exists on a replacement physical disk that you install in a system. A secured
foreign conguration is a RAID conguration that was created under a dierent security key.
There are two scenarios in which a secured foreign import fails:
• The passphrase authentication fails—A virtual disk secured with a security key dierent from the current controller security key
cannot be imported without authentication of the original passphrase used to secure them. Supply the correct passphrase to import
the secured foreign conguration. If you have lost or forgotten the passphrase, the secured foreign disks remain locked (inaccessible)
until the appropriate passphrase is entered or if they are erased.
Troubleshooting
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