Host Disk Full - but it's not

[Soundman32]

Latest VirtualBox 4.2.12
Windows7 64bit host (500GB drive, 1 partition C: NTFS, 95GB free).


I've created a VM (Fedora 14) that uses a differencing disk. The differencing disk is a dynamic SATA 8GB (currently at 8KB), the source disk is about 6GB.

When I start the VM for the first time, halfway through the Linux boot process, I get a host disk full message:

Either:

An error has occurred during virtual machine execution! The error details are shown below. You may try to correct the error and resume the virtual machine execution.



The I/O cache encountered an error while updating data in medium "ahci-0-0" (rc=VERR_DISK_FULL). Make sure there is enough free space on the disk and that the disk is working properly. Operation can be resumed afterwards.

Error ID: BLKCACHE_IOERR
Severity: Non-Fatal Error

or

An error has occurred during virtual machine execution! The error details are shown below. You may try to correct the error and resume the virtual machine execution.

Host system reported disk full. VM execution is suspended. You can resume after freeing some space.

Error ID: DevAHCI_DISKFULL
Severity: Non-Fatal Error

[mpack]

As a general rule, error messages should be believed. Stop suspecting a VBox bug, and start suspecting a mistake in your assumptions.

If you want to discuss this further then post the log file from the VM. See Minimum information needed for assistance.

[Soundman32]

VM Info as requested

[Soundman32]

Log file.

Interesting bit:

00:00:21.909547 Guest Additions information report: Version 4.2.12 r84980 '4.2.12'
00:00:21.909613 Guest Additions information report: Interface = 0x00010004 osType = 0x00053000
00:00:21.909856 Guest Additions capability report: (0x0) seamless: no, hostWindowMapping: no, graphics: no
00:00:21.909933 Guest reported fixed hypervisor window at 0x00000000e1800000 (size = 0x800000, rc = VINF_SUCCESS)
00:00:21.913794 Guest Log: vboxguest: major 0, IRQ 9, I/O port d020, MMIO at 00000000f0400000 (size 0x400000)
00:00:23.399342 AIOMgr: Preparing flush failed with VERR_NOT_SUPPORTED, disabling async flushes
00:00:23.413536 I/O cache: Error while writing entry at offset 143654912 (4096 bytes) to medium "ahci-0-0" (rc=VERR_DISK_FULL)
00:00:23.413606 VM: Raising runtime error 'BLKCACHE_IOERR' (fFlags=0x6)
00:00:23.413619 Changing the VM state from 'RUNNING' to 'SUSPENDING'.
00:00:23.413654 PDMR3Suspend: after 0 ms, 1 loops: 1 async tasks - ahci/0
00:00:23.554298 AIOMgr: Endpoint for file '\VirtualMachines\harddisksrack1_pri_hd.vdi' (flags 000c0781) created successfully
00:00:23.588976 PDMR3Suspend: 175 342 157 ns run time
00:00:23.589004 Changing the VM state from 'SUSPENDING' to 'SUSPENDED'.
00:00:23.590995 Console: VM runtime error: fatal=false, errorID=BLKCACHE_IOERR message="The I/O cache encountered an error while updating data in medium "ahci-0-0" (rc=VERR_DISK_FULL). Make sure there is enough free space on the disk and that the disk is working properly. Operation can be resumed afterwards"

[mpack]

This is the bit that interests me:

00:00:00.682513 File system of '\VirtualMachines\harddisksrack1_pri_hd.vdi' is ntfs

Note non-standard path to VDI, and lack of drive letter. What drive is this addressing?

[Soundman32]

I've opened rack1_rtr_pri.vbox and VirtualBox.xml but I can't find the media configuration file.

I've attached the rack1_rtr_pri.vbox file. No mention of a drive-less path, but also, no mention of the HD in the media registry. Is this normal for a differencing drive?

<MediaRegistry>
<HardDisks/>
<DVDImages/>
<FloppyImages/>
</MediaRegistry>

An image is mentioned later on, but I can't find any reference to the uuid in VirtualBox.vbox

<StorageControllers>
<StorageController name="SATA0" type="AHCI" PortCount="30" useHostIOCache="false" Bootable="true" IDE0MasterEmulationPort="0" IDE0SlaveEmulationPort="1" IDE1MasterEmulationPort="2" IDE1SlaveEmulationPort="3">
<AttachedDevice type="HardDisk" port="0" device="0">
<Image uuid="{45f02997-ea1d-47b0-aa54-72a6448f1971}"/>
</AttachedDevice>
</StorageController>
</StorageControllers>

[mpack]

In VirtualBox since v4.x, the "Media Registry" resident in memory is the union of all the local media registers in each .vbox file plus VirtualBox.xml (the latter only for backwards compatibility purposes - v4.x does not put anything there).

If you don't find the media registered in the .vbox file or VirtualBox.xml, then this VM must be accessing media belonging to another VM. You'll find the media registered in the .vbox file of the other VM. Needless to say, this is not a recommended arrangement of data. And note that this disk is being used as the primary boot drive in the VM which doesn't actually own this media.

You should also check whether the file has been write protected.

[mpack]

Perhaps you should simply make a full clone of this VM, that would ensure that the clone is stand alone, with legal file paths and all files in their proper place.