How to work with damaged HDDs in a RAID
The Data Extractor Express RAID Edition can work with two damaged HDDs connected to PC-3000 Express ports within one task at the same time. The total number of the connected HDDs can be increased by using motherboard ports and file-images.
Crucial features for working with damaged HDDs of a virtual RAID:
- Ability to make a full or partial data copy from any HDD included in the RAID
- Ability to define and use a virtual translator for any HDD in the RAID or the whole virtual RAID
- Ability to manage and interact with the specialized PC-3000 UDMA utility for HDDs connected to the PC-3000 UDMA ports (power supply management, reset commands, choice of reading command etc.)
- Advanced features for working with SCSI and SAS storage devices (full control over reading parameters, choice of reading command, building the head map etc.)
- Ability to skip the damaged HDD while defining the array configuration or to use data taken from a copy
- Redundancy usage with the purpose of data recovery from the problematic HDDs
- Integrated logical analysis features that allow for reading only the minimally necessary amount of data from the storage device, thus reducing the load and increasing the chances of successful recovery
Before the Data Extractor UDMA RAID Edition appeared, you would have had to have made a full sector-by-sector copy of the data from the simple stripe if one of its members was physically damaged and could not be connected in a standard way, or it would not have been possible to get access to its sectors without using the PC-3000 UDMA or PC-3000 SAS methods. You could only have attempted to recover the user data after creating a copy.
Taking into account the significant capacity of high end HDDs and possible issues with a full copy of the damaged drive, the Data Extractor UDMA RAID Edition provides a unique approach:
- Open the Virtual RAID in the Data Extractor Explorer and get an understanding of the data organization in the virtual RAID.
- Build a map of the required data. It can be a map of used sectors, a data map of the required catalogs, a necessary file map, or a metadata map.
- For the built map, build a “Sub-map” of sectors to be read from the damaged HDD.
- Make a sector-by-sector copy only of these required sectors by using the Data Extractor.
How to define the array configuration
RAID configurations can be very complex and data recovery from RAID is not easy even if the configuration appears to be simple. It can be difficult to define the correct order of HDDs, the block size and the initial shift.
Key features of the Data Extractor UDMA RAID Edition for defining the array configuration:
- Unique auto-detection mode for a wide range of configurations. This mode is based on the analysis of file systems and user data
- Powerful interactive mode that allows for easily defining unusual configurations, and very flexible automatic operations with an ability to control the current result
- Useful search tools help define numerous RAID parameters including detecting the size and reviewing the file system structures, metadata with disk structure (MBR, GPT etc.), including the metadata with the virtual RAID organization (mdadm RAID superblock), and analysis of the information from LDM
- Array parameters can be defined without touching defective HDDs
How to assemble a RAID and logically recover data
Even if you know the full configuration of a RAID and there are no problems with the damaged HDDs, recovering data from a RAID can be a complicated task for multiple reasons: a large number of drives which need to be connected simultaneously, slow read speeds, impossibility to assemble an unusual array configuration, or logical damage.