'Device is disabled' after power failure.


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Hi Guys,

 

My power went out last night causing my unraid to be shutdown improperly, after powering back up I've got a disk showing 'Device is disabled, contents emulated' and I can't work out why.

 

'df -h' shows the disk is mounted and I can browse the contents from the command line.

 

Smart long test passed OK, unraid is at v6.3.5.

Smart log attached.

 

Thanks in advance!

WDC_WD10EAVS-00D7B1_WD-WCAU49540378-20170628-1710.txt

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When a disk is kicked from the array due to a failure to access the drive or complete a write, unRAID will kick it from the array and emulate it. Often the root cause is traced back to a bad or loose cable, which is quite likely if this is what happened.

 

When a server boots, by default it will start the array automatically if all of the drives are recognized and configuration is valid. Otherwise it will wait for the user to take some action. There is a setting that will cause unRAID to never start the array on boot, and wait for the user do start it after verifying looks good. I recommend making that setting change. Click on disk settings and the very first option is "Enable Auto Start". Set to "No". This gives you the ability to make sure all looks good before starting the array, and can avoid auto-starting under a variety of situations where you do not want it to autostart. Since most of us leave our servers run 24x7, the extra step to manually start the array on the occasional boot is not a problem.

 

But even if auto-start is enabled, unRAID will not start the array if it detects a configuration change - including a disk that did not get recognized on boot. The disk will show missing on the main unRAID tab, along with some warning near the start button that starting the array will result in a disk being disabled and emulated. If ever you see that, DO NOT start the array. If you power down, recheck / replace the cable to that disk, and reboot, the disk will be recognized and you'll be able to start the array normally. THE FACT YOU BOOT AND A DISK IS NOT RECOGNIZED DOES NOT KICK THE DISK. Only starting the array afterwards kicks the disk.

 

So I am not clear if the disk kicked BEFORE your hard shutdown, or occurred when you started the array afterwards. But either way, it is very likely a bad or loose cable, and left uncorrected, it will happen again.

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I tried rebuilding to the same drive as johnnie suggested but the web gui became unresponsive and the syslog was showing drive access errors.

 

I had a new motherboard and CPU ready that I had been planning an upgrade with, I used this as an opportunity to install the new hardware and tidy/check all drive connections, upon boot of the new system I tried a rebuild to the same drive again and it's just completed successfully.

 

Thanks for all of your advice.

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Good deal. Nothing is more important to a smooth running server than good cabling! Drive cages are a really good ideas as they allow swapping disks without risking knocking something askew (which is incredibly easy to do when sticking your hand into the delicate wiring).

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