Error 500 when running rsync

Having added a new additional disk to my setup. I want to run rsync to 'mirror' the data from the first disk. However when I run the job I get an error

I don't see much more info in the syslog. Can anyone suggest what might be going wrong here?

Ah thanks voted, I didn't't know that. Here id the full message:

Failed to execute command 'export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev --getsize64 '/dev/sda' 2>&1' with exit code '1': blockdev: cannot open /dev/sda: No such device or address

OMV\ExecException: Failed to execute command 'export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev --getsize64 '/dev/sda' 2>&1' with exit code '1': blockdev: cannot open /dev/sda: No such device or address in /usr/share/php/openmediavault/system/process.inc:197

Stack trace:

#0 /usr/share/php/openmediavault/system/blockdevice.inc(258): OMV\System\Process->execute(Array)

#1 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(87): OMV\System\BlockDevice->getSize()

#2 [internal function]: Engined\Rpc\DiskMgmt->enumerateDevices(NULL, Array)

#3 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#4 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(123): OMV\Rpc\ServiceAbstract->callMethod('enumerateDevice...', NULL, Array)

#5 [internal function]: Engined\Rpc\DiskMgmt->getList(Array, Array)

#6 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#7 /usr/share/php/openmediavault/rpc/serviceabstract.inc(149): OMV\Rpc\ServiceAbstract->callMethod('getList', Array, Array)

#8 /usr/share/php/openmediavault/rpc/serviceabstract.inc(588): OMV\Rpc\ServiceAbstract->OMV\Rpc\{closure}('/tmp/bgstatus4H...', '/tmp/bgoutputlb...')

#9 /usr/share/php/openmediavault/rpc/serviceabstract.inc(159): OMV\Rpc\ServiceAbstract->execBgProc(Object(Closure))

#10 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(150): OMV\Rpc\ServiceAbstract->callMethodBg('getList', Array, Array)

#11 [internal function]: Engined\Rpc\DiskMgmt->getListBg(Array, Array)

#12 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#13 /usr/share/php/openmediavault/rpc/rpc.inc(86): OMV\Rpc\ServiceAbstract->callMethod('getListBg', Array, Array)

#14 /usr/sbin/omv-engined(537): OMV\Rpc\Rpc::call('DiskMgmt', 'getListBg', Array, Array, 1)

#15 {main}

If you look again you will see that the message does match the screen shot, at least the first to linger off the error message.

Anyway, may be that's academic now since I did some updates and a reboot and now I don't see the message.

However the rsync job just hangs now.

The reason I thought it had hung is because the GUI output just stopped at the second file it was supposed to be copying, and there was no evidence of any files at the destination.

However are some reboots I am getting this output snippet

sending incremental file list
rsync: [generator] failed to set times on "/srv/dev-disk-by-uuid-f3b421dd-d2ac-49f6-bd07-ac2a95c42e32/Mirror/My Backup/TempDiskBackup/MISC/White horse/100MEDIA": Read-only file system (30)

After a good few attempts it has written some files to the destination but mostly it has not.

Time to look at the disk...

Now when I go to look at the disks the GUI gives me this just like before.

Failed to execute command 'export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev --getsize64 '/dev/sda' 2>&1' with exit code '1': blockdev: cannot open /dev/sda: No such device or address

OMV\ExecException: Failed to execute command 'export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev --getsize64 '/dev/sda' 2>&1' with exit code '1': blockdev: cannot open /dev/sda: No such device or address in /usr/share/php/openmediavault/system/process.inc:197

Stack trace:

#0 /usr/share/php/openmediavault/system/blockdevice.inc(258): OMV\System\Process->execute(Array)

#1 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(87): OMV\System\BlockDevice->getSize()

#2 [internal function]: Engined\Rpc\DiskMgmt->enumerateDevices(NULL, Array)

#3 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#4 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(123): OMV\Rpc\ServiceAbstract->callMethod('enumerateDevice...', NULL, Array)

#5 [internal function]: Engined\Rpc\DiskMgmt->getList(Array, Array)

#6 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#7 /usr/share/php/openmediavault/rpc/serviceabstract.inc(149): OMV\Rpc\ServiceAbstract->callMethod('getList', Array, Array)

#8 /usr/share/php/openmediavault/rpc/serviceabstract.inc(588): OMV\Rpc\ServiceAbstract->OMV\Rpc\{closure}('/tmp/bgstatuskB...', '/tmp/bgoutputQ0...')

#9 /usr/share/php/openmediavault/rpc/serviceabstract.inc(159): OMV\Rpc\ServiceAbstract->execBgProc(Object(Closure))

#10 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(150): OMV\Rpc\ServiceAbstract->callMethodBg('getList', Array, Array)

#11 [internal function]: Engined\Rpc\DiskMgmt->getListBg(Array, Array)

#12 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#13 /usr/share/php/openmediavault/rpc/rpc.inc(86): OMV\Rpc\ServiceAbstract->callMethod('getListBg', Array, Array)

#14 /usr/sbin/omv-engined(537): OMV\Rpc\Rpc::call('DiskMgmt', 'getListBg', Array, Array, 1)

#15 {main}

Sda1 is the source device for the rsync copy. I've little to no experience in Linux let alone filesystems so it's hard for me to interpret the errors. Also I do not know what the 'proper partition' would be.