How to get dmraid to rebuild with a new disk?

**kuja** · June 19th, 2009

Originally Posted by skralljt

Does anybody have any suggestions for me?

I suggest not using RAID0 if data integrity is required, and/or if complete backups are unavailable. Maybe look into RAID 5/6 or RAID 0+1 if you want performance and integrity.

**madhusker** · July 5th, 2009

Originally Posted by CowEyeball

I am in a similar situation as this gentleman. After wrestling with Error messages during bootup, despite what otherwise seemed to be a perfectly functioning RAID1 setup, I resorted to disconnecting each of the drives and booting off of one drive in turn to ensure things were in fact behaving properly.

The good news is that they were, hooray!

The bad news is that now my BIOS is insisting my RAID is "degraded" and I am at a loss as to how to make it happy again. My Motherboard, an Abit AS8, appears to only have Windows software to perform a rebuild. Obviously this isn't an option for me, so I'm hoping dmraid can pull off the same.

Trying to rebuild one of the drives through dmraid isn't working for me though, I consistently receive this message:

Code:

root@cowbox:/dev# dmraid -R isw_cajbjfhdch /dev/sdb
Volume "isw_cajbjfhdch_COWBOX_RAID1" is not in rebuild state (current: 0)
Rebuild: cannot rebuild from current state!

Any pointers?

I have the Asus P6T Deluxe version 2 with the same problem. It appears that even in 1.0.0.rc15 dmraid does not support a rebuild. Looks like it's back to software mdadm and md devices. Bummer...

**CowEyeball** · July 5th, 2009

I wish I knew how to do that! I ended up using an IDE hard drive and putting Windows on it. I booted into Windows, installed the Intel RAID garbage, and it rebuilt my RAID something awesome. When it finished I restarted again, changing the BIOS to never boot into that drive again, and now everything is working great.

I may get my linux license taken away for doing this, but at least the RAID is healthy again.

**ronparent** · July 6th, 2009

CowEyeball

Great!!! It looks like you go lucky, but I'll keep your solution in mind for my own raid0 drives if I run into trouble. You are using raid0 aren't you?

**CowEyeball** · July 6th, 2009

Originally Posted by ronparent

CowEyeball

Great!!! It looks like you go lucky, but I'll keep your solution in mind for my own raid0 drives if I run into trouble. You are using raid0 aren't you?

Actually I'm using raid1, but hopefully that wouldn't matter. Upon installing the Intel RAID manager software it literally took off immediately and didn't ask me any questions. It found the RAID, saw it was sick, and fixed it. Lucky indeed.

Two things worth noting, the Intel RAID management software on the Abit site was incorrect! I'd advise anyone interested in going this route to determine the chipset of their board and get the software directly from Intel's site.

Secondly, and this may be a no-brainer for those more experienced than me, it took several hours to rebuild the RAID. Although not surprised in retrospect, it was a stressor when it was happening.

**ronparent** · July 6th, 2009

Raid1 is a so called mirroring raid and has built in redundancy. If one disk goes bad rebuilding is expected. Raid0 is called stripped array. If one disk goes bad, tough, There is no rebuilding or recovery of data. Your'e lucky. You are using the safer raid alternative.

**CowEyeball** · July 6th, 2009

Ah right, duh. So on a RAID0 if one disk dies you're starting over anyway? Seems right. I chose RAID1 intentionally because of the redundancy. It makes our family fileserv seem that much more "hardcore", "safe", and "amazing".