Tecnopolis Enterprises is pleased to offer a service to help those who have just experienced a two drive failure on a linux software RAID 5 array. We recently experienced this horrible event on one of our own servers and discovered that all hope is not lost. It took 4 days but we recovered nearly every byte of data off a 3 160GB disk (320GB) RAID 5 array after two drives suffered "soft" failures (growing bad sectors), including hosed parition tables and a corrupted root directory!
If you have had a RAID 5 (or RAID 0) crash and you need your data, and you believe at least one of the disk failures is simply a "soft" failure then there is a good chance that much of your data can be retrieved. In reality, all you should lose are the parts of the disk where there are bad sectors. A soft failure is a situation where the disk still spins and is recognized by the BIOS and by the kernel but for some reason was taken offline by the RAID subsystem. This is usually simply the growth of some new bad sectors and the slow deterioration of the drive surface.
Most data recovery companies are of the "if you have to ask you can't afford it" variety. In contrast, depending on your situation, it may only cost you several hundred dollars (CAN$) to recover your data with Tecnopolis.
To help those who are linux gurus and want to have a shot at it themselves, here's information on what we do. The best thing to do is instantly remove the drives that make the array. That ensures they don't get worse in the meantime. What we would do next is use dd to duplicate the failing drives to temporary drives. This can be problematic if the drives generate IDE errors when reading some sectors. Once we have a reasonable reproduction of your disks, we run a raid recreation command to try to get the array back up in degraded mode. From there it's a matter of mounting RO and seeing if we get lucky. At this point you can run into situations where the partition table or root directory have been corrupted by bad sectors. There are ways around that as well, depending on your configuration. As a last resort, we can run custom disk scanning programs to look for the most critical individual files.
The bottom line is, there's a good chance your data can be saved. If your data is critical to you (and you wouldn't be reading this if it weren't), then let us try to help you. Since we operate on copies of your disks only, there will be little if any degradation of your original disks, giving you the option of sending the array to one of the pricier recovery services if needed. If we can't recover your data, there is only a small diagnosis fee and shipping charges.
Email raidrecover19@tecnopolis.ca with any inquiries or for more details.