RNDU4000 disaster recovery?

elliot_pl wrote:

Hi, I'm planning to buy Ultra4 for home use. I will definitely use XRaid. Of course - backup must be done frequently, but let's assume some sort of failure of ReadyNas itself after a warranty. Let's also assume that HDD's are fine. Is there a way to recover data from disks managed by XRaid? And I'm talking 3 or 4 disks in one volume. Is it even possible to put drives to another (healthy) ReadyNas? What are the options? Cheers, Elliot

Yes, you can put the drives in another ReadyNAS as long as it's running the same architecture.

And what about other options? Is mounting XRaid drives under linux possible for data recovery?

elliot_pl wrote:
And what about other options? Is mounting XRaid drives under linux possible for data recovery?

Yes, you can use Linux to do the recovery.

Wow - very quick response for the second time :) Thank you for that.

So one more question - if I understood correctly, XRaid is basically plain mdraid or something else?

It is a customized version of Raid as it is expandable both horizontally (adding disks) and vertically by increasing the size of the disks (one at a time). The expansion vertically will not take place until there are enough of the larger size for redundancy. In the case of a 4 bay unit that's two. For example my NVX units started out with 4x1TB drives (2.7TB net volume after redundancy and overhead). As I was filling up the volume, I replaced two to the 1TB drives with 3TB drives in both units and the net volume is now 4.5TB. (Note: Sparc based volumes will not expand until all drives are larger).

The correct name for the technology in the Ultra 4 is X-Raid2. Here is a description of the expansion of X-Raid2. The original Sparc based units had X-Raid and X-Raid2 is far more flexible.

Thank you for the answer. Yes, I'm aware that this is custom solution compared to traditional RAID. I have no questions regarding expanding XRaid2. I was rather wondering how to extract data from drives managed by it. yoh-dah wrote that it is possible under Linux. Right now I'm wondering how because you PapaBear confirmed that this is non-standard mdraid solution.

On x86 it's using mdadm to stop and start the RAID. It's using md raid. The X-RAID2 scripts are custom and proprietary though.

Sparc uses a custom mdconfig for Flex-RAID, but not x86 or ARM. x86 and ARM use md raid for both X-RAID2 and Flex-RAID.

You might want to have a read of this thread: http://www.readynas.com/forum/viewtopic.php?f=65&t=61168

Yes - that finally does it. This URL is what I was looking from the beginning. Thank you guys!
I really appreciate the help.