Yesterday, my disk 11 all of a sudden came up as disabled (red).  Nervous about losing the data, I purchased a new disk (to go through a data rebuild of disk 11).  I powered down the array, and replaced disk 11 with the new disk.  When I powered on the array, it came up with the message about "Start Array/Rebuild Data"... I selected YES, the machine went to "starting array" then froze... no telnet, no web interface.  After awhile I powered down the machine.  I powered it up several times, and could not get the web interface running, and telnet was iffy (worked, then lost connection, etc)... After several attempts it did start up and actually started rebuilding drive 11.... it only did this for a few minutes, then web interface went back to "Started," and again the disk 11 icon is red.  It appears that I can read from disk 11, although I think it is actually reconstructing on the fly.... Unraid never formatted my disk 11, nor was there enough time to reconstruct 400G of data.

 

Any ideas?  I am running v4beta9.

 

 

After a few reboots, it now appears to be rebuilding data correctly.

 

 

How are you connecting your hard drives?  If via mobile rack/backplane, check that the drive is well seated.  Also check cabling.  Also upgrade to 4.1