Any way to recover data from a corrupted RAID 6 array?

Solution 1:

Since RAID 6 stripes data over multiple devices, this looks like one of the devices is missing from the array, and the RAID controller doesn't realize it is missing a device. This means every continuous stream of data has missing data in it.

Running chkdsk can only make things worse, since the issues are below the actual filesystem.

You would somehow need to fix the array configuration so that all devices are properly in the array. I don't know how to actually do that within the MegaRAID system.

Before anything else, I would recommed getting an image of every hard drive to a separate medium, so that no new writes would corrupt the system further.

Although it is also possible that the data is already corrupted in unrecoverable ways.