[SOLVED] Unable to stop array, disk 1 will not unmount

I've been running Unraid 4.7 with mysql on my first server for about 2 weeks (1 week with mysql installed). Server has 2 x data disks (no parity disk yet).

I have been using the powerdown script to shut down the server (which has been working perfectly).

However today I needed to stop the array to make some changes .When I click stop in the control panel, disk 2 will unmount, but disk 1 will hang on unmounting and the server locks up. I have to run the powerdown script from the command line and shut the server down.

I did some searching and discovered that something is obviously running on disk 1 and preventing it from unmounting.

I found some instructions to identify the offending process:

/usr/bin/fuser -mv /mnt/disk* /mnt/user/*

The result:

             USER    PID          ACCESS        COMMAND
/mnt/disk1: root     1844         F.c..         mysqld

So ...Mysql is stopping disk 1 from being unmounted.

So I found this to stop mysql running:

killall mysqld

I ran it and it then I re-ran:

/usr/bin/fuser -mv /mnt/disk* /mnt/user/*

and it simply returned me to the prompt, so I assumed this meant nothing was running.

I went to the control panel and clicked stop, this time expecting the array to stop, but again it hung on unmounting disk 1, exactly as before.

So now I do not know how to proceed.

Here is the tail end of the log file where it hung:

Aug  4 06:37:12 NAS status[2698]: State: STARTED
Aug  4 06:37:12 NAS status[2698]: D#           Model / Serial          Status         Device    
Aug  4 06:37:12 NAS status[2698]: 0      rdevModel.0 / rdevSerial.0    DISK_DSBL_NP   rdevName. 
Aug  4 06:37:12 NAS status[2698]: 1  WDC WD20EARS-00 / WD-WCAZA3646980 DISK_OK        sda       
Aug  4 06:37:12 NAS status[2698]: 2  WDC WD10EADS-11 / WD-WCAV53474284 DISK_OK        sdb       
Aug  4 06:37:12 NAS status[2698]: SMART overall health assessment
Aug  4 06:37:12 NAS status[2698]: /dev/sda: smartctl 5.39.1 2010-01-28 r3054 [i486-slackware-linux-gnu] (local build)
Aug  4 06:37:12 NAS status[2698]: Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net
Aug  4 06:37:12 NAS status[2698]: SMART overall-health self-assessment test result: PASSED
Aug  4 06:37:12 NAS status[2698]: /dev/sdb: smartctl 5.39.1 2010-01-28 r3054 [i486-slackware-linux-gnu] (local build)
Aug  4 06:37:12 NAS status[2698]: Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net
Aug  4 06:37:12 NAS status[2698]: SMART overall-health self-assessment test result: PASSED
Aug  4 06:37:12 NAS status[2698]: /dev/sdc: smartctl 5.39.1 2010-01-28 r3054 [i486-slackware-linux-gnu] (local build)
Aug  4 06:37:12 NAS status[2698]: Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net
Aug  4 06:37:12 NAS status[2698]: /dev/sdc: Unknown USB bridge [0x0718:0x0533 (0x100)]
Aug  4 06:37:12 NAS status[2698]: Smartctl: please specify device type with the -d option.
Aug  4 06:37:12 NAS status[2698]: Use smartctl -h to get a usage summary
Aug  4 06:37:13 NAS status[2698]: No active PIDS on the array
Aug  4 06:37:14 NAS rc.unRAID[2723]: Killing active pids on the array drives
Aug  4 06:37:14 NAS rc.unRAID[2733]: Umounting the drives
Aug  4 06:37:14 NAS rc.unRAID[2737]: umount: /mnt/disk1: device is busy
Aug  4 06:37:14 NAS rc.unRAID[2737]: umount: /mnt/disk1: device is busy
Aug  4 06:37:14 NAS rc.unRAID[2739]: Stopping the Array
Aug  4 06:37:14 NAS kernel: mdcmd (13): stop 
Aug  4 06:37:14 NAS kernel: md: 2 devices still in use.
Aug  4 06:37:15 NAS emhttp: shcmd (36): umount /mnt/disk1 >/dev/null 2>&1
Aug  4 06:37:15 NAS emhttp: _shcmd: shcmd (36): exit status: 1
Aug  4 06:37:15 NAS emhttp: shcmd (37): rmdir /mnt/disk1 >/dev/null 2>&1
Aug  4 06:37:15 NAS emhttp: _shcmd: shcmd (37): exit status: 1
Aug  4 06:37:15 NAS emhttp: Retry unmounting disk share(s)...

Can someone give me a hand with where to go from here.

Thanks

Fixed it myself.

It turned out to be the swapfile that I had forgotten I had setup that was still active and stopping the drive from unmounting.

Unmenu > User Scripts > Disable Swapfile, and the disk could unmount normally.