Forensic RAID Support

To help with creating a forensic RAID image of an array with an unknown configuration, Atola TaskForce is now equipped with a RAID assembly, configuration autodetection and imaging capability.

What is currently supported:

• RAID types: RAID 0, 1, 5, 10 and JBOD
• File systems: NTFS, ext4/3/2, XFS, exFAT, APFS, HFS/HFS+, FAT32/16

How it works

1. Select sources that make up a RAID array (SATA/SAS/USB drives, raw, E01 or AFF4 image files)
2. Wait a few minutes for a Possible configuration hint to pop up
3. Click Apply
4. Click Go to Image and acquire the whole array or partitions within

Watch all RAID screencasts

• Autodetecting and imaging RAID 0
• RAID 5 imaging with a missing device
• Imaging RAID 5 array with errors
• Imaging RAID 10 with Atola TaskForce
• Imaging selected partitions of a RAID array
• Instant autodetection of an mdadm-created RAID

Automated assembly of RAID with an unknown configuration

Autodetection module starts running immediately upon the selection of the RAID devices (or images).

• In Stage 1, it reads data on the drives to identify the RAID type which will narrow down the number of combinations for Stage 2.
• in Stage 2 goes through thousands and even millions of possible configurations to identify suitable ones.

If you know the configuration, you can enter it manually.

Autodetection uses heuristic algorithms to help avoid tedious manual work while searching for:

• RAID type
• device order
• block size
• block order

Maximum allowed number of RAID parameter combinations to check is 100,000,000. With 12 possible block (stripe) sizes ranging from 512 bytes to 1 MB, the current limit enables TaskForce to check all possible RAID configurations for:

• 9 devices in RAID 5 array (17,418,240 variants)
• 10 devices in RAID 0 array (43,545,600 variants)

After you apply the suggested configuration with one click on a button, drives are arranged into the correct order, RAID type and other configurations are automatically applied, and file systems are searched for.

Reassembling and imaging RAID 5 with a missing device

If you are reassembling RAID 5, and one of RAID 5 drives is missing or is heavily damaged, TaskForce allows you to select all available drives (or images thereof) and click Add missing device button underneath the list of drives and/or images.

TaskForce uses the redundancy inherent to RAID 5 to identify the configuration and create a full image of the RAID even in the absence of one of the RAID's parts.

Starting from firmware version 2022.10, TaskForce automatically detects and reassembles RAID 5, even when the user doesn’t specify that one drive in the array is missing.

Imaging RAID 5 with errors

When the Autodetection module parses the data on the drives to identify the RAID configration and encounters errors, error tags are displayed next to the respective RAID member. Despite the errors on drives, TaskForce is able to mount the partitions of the RAID for preview using data redundancy of this RAID.

During imaging, when an error is encountered, TaskForce automatically reconstructs the missing data on the fly. It uses the data in the parity blocks on the remaining members of the RAID. This process is seamless, needs no involvement of the operator and allows recovering the full image.

RAID 10 autodetection and imaging

RAID 10 arrays combine mirroring and striping techniques. That is why these arrays have higher performance and better resiliency against data loss or corruption.

TaskForce uses both of these advantages: it images data faster from a RAID 10 compared to other RAID types and rebuilds the image using the data redundancy in case of disk failure. TaskForce can achieve 900 MB/s on a RAID 10 consisting of SSD drives and 400 MB/s on one made up of HDD drives.

After you have selected the drives that make up the RAID 10 array, the RAID configuration autodetection module identifies the RAID type. The final configuration is suggested after variant checks of other parameters.

When you apply the suggested configuration, TaskForce shows the members of the RAID 10 in groups according to the pair of mirrors found in this array.

The found partitions and their contents are displayed in the Partition preview part of the screen. Browse through the folders to see if the contents of the RAID are potentially helpful in your investigation. Then proceed to imaging.

RAID partition preview

Any change in RAID configuration you perform manually or by applying the suggestion produced by the Autodetection prompts the bottom Partitions panel to refresh. If the configuration is correct, file systems are found and validated, you see partitions and their contents.

Instant configuration detection using RAID metadata

TaskForce instantly identifies mdadm-created RAID arrays with great precision by detecting controller metadata. These types of arrays are mounted in a matter of seconds and do not require a manual selection or application.

TaskForce’s autodetection module is able to detect the Start LBA parameter for different types of mdadm RAID arrays.