Disk1 dead -- degraded mode won't boot

[terpstra]

My ReadyNAS NV (not +) has 4x 7 ST3750640AS and a 1GB RAM chip. Disk 1 is dead. The device will not start in degraded mode.

Sequence of events:
1. ReadyNAS ran out of memory (according to ssh to NAS running dmesg+free)
2. Rebooted readyNAS
3. ReadyNAS failed to start
4. Pulled out each disk in turn and tested them in PC with SMART self-test and dd if=/dev/sdb of=/dev/null.
5. I saw valid partitions on disks 3+4 (disk 2 seems to be parity).
6. Conclusion of step #4: all disks are fine except disk 1 which has unrecoverable failures within the first partition (firmware)
7. Put disks 2,3,4 back into ReadyNAS. Packaged up disk1 for RMA.
8. Started ReadyNAS with disk 1 slot empty
9. ReadyNAS still fails to boot
... I would have expected the system to boot in degraded mode.

Additional facts:
1. RAIDar from Windows 7 sees the device
2. The web+ssh servers do not appear to be running
3. It responds to ping
4. The power LED pulses continually
5. The device is louder than before (perhaps altered airflow from missing disk?)
6. I do not have a spare 750GB disk.

When the replacement arrives can I just plug it in and expect it to work?
Can I convince it to operate in degraded mode before then?
I noticed disk 3+4 use LVM. If I ever need to do manual data recovery, could I just XOR disk2+disk3+disk4 to reconstruct disk1 and then mount the volume group?

[Leia]

Which raid type do you created? XRAID-2 or flex-RAID? And which raidiator version do you installed?

[mdgm-ntgr]

The Infrant ReadyNAS NV is Sparc, so it would be either X-RAID or Flex-RAID depending on what terpstra chose.

[terpstra]

It is X-RAID running v4.01c1-p5.

Back to my question, though:
Should it have been able to boot without disk 1 or not?

[mdgm-ntgr]

4.01c1-p5 is also known as 4.1.5 and was released back in April 2009: http://www.readynas.com/RAIDiator_4_1_5_Notes

Using X-RAID the NAS boots off the OS partition on disk 1 (/dev/hdc1) but the OS partition is also on the other disks. I think I read somewhere that the NAS may fail to boot if disk 1 fails and that replacing the dead disk should solve the issue but I can't find where I read that.

[Thomas_xh1]

Hi, terpstra

Answer for your question,
Yes, you unit would be start with degrade mode without disk 1, but the disk 2, disk 3 and disk 4's super block must be synced,

If the system still cannot boot without disk 1, maybe there are another disks still has errors, so it would not be start.

I did not know whether your unit within warranty, you can reboot this unit to telnet mode and contact regional supprt engineer, or PM telnet information to me.