Questions tagged [qcow2]
The qcow2 tag has no summary.
30 questions
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libvirt: "Error starting domain: internal error: failed to parse JSON: nesting too deep"
I'm on Fedora Linux 42.20250824.0 (Sway Atomic), running libvirt version 11.0.0, qemu-img version 9.2.4 (qemu-9.2.4-1.fc42) and virt-manager version 5.0.0, all installed as layered packages.
Using ...
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Is it possible to recover deleted files from a qcow2 disk in Proxmox using extundelete or ext4magic?
I’m running a Proxmox VM with a qcow2 disk (Ubuntu guest, ext4 filesystem). I tried to recover a recently deleted file using extundelete and ext4magic, but both tools failed to find the file, even ...
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QEMU-KVM: how to see contents of top layer qcow2 image only (revert some back to backing image contents)?
I use kvm/qemu on Linux and usual setup is having backing image and running top image that tracks changes (qemu-img create -f qcow2 -F qcow2 -b backimage topimage). I'm concerned with growth of those ...
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Is possible to resize a qemu/libvirt image maintaining virtual size and at same time don't lose data?
Is possible to resize a qemu/libvirt image maintaining virtual size and at same time don't loss data? I explain better:
when you create a virtual disk
qemu-img create -f qcow2 debian-GEN.qcow2 60G
...
- 14.3k
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Run qcow2 image created with virt-manager using qemu-system-x86_64
My qemu version is QEMU emulator version 9.0.2 (Debian 1:9.0.2+ds-2+b1).
I created a FreeBSD 14 VM using virt-manager. It's drive is a qcow2 image:
-rwxr-xr-x 1 libvirt-qemu libvirt-qemu 8.1G 20240916 ...
- 359
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Need to use .qcow2 VM file format but only have VirtualBox
I only have VirtualBox.
I have a .qcow2 image I need to use.
VirtualBox supports several file formats, but not .qcow2
What are my options?
I'd much prefer not have to change to a different hypervisor.
- 139
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Limiting the file size of .qcow2 files [closed]
Qcow 2 files are an open source file format for virtual machines. In my opinion, unlike .vmdk files, they do not offer the option of specifying a maximum file size. This means that they can constantly ...
- 139
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Write QCOW2 image to iSCSI LUN?
I've been trying to write a QCOW2 image to an iSCSI LUN target but have been unsuccessful. Based on this link, this should be possible (and should be possible without having to mount the iSCSI LUN as ...
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Why is it recommended to add nodatacow to a VM image on BTRFS, but using a QCOW2 disk is ok?
As far as I know, it is recommended to disable copy on write for VM images to avoid performance degradation on BTRFS. However, no one recommends against using qcow2 disk image format, despite being a ...
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Delete snapshots only in libvirt, but retain them in qcow2
I executed the following commands
-- 12:18:40 sudo virsh snapshot-delete Windows-10-128GB 2022-04-12-Pre-Activation
Domain snapshot 2022-04-12-Pre-Activation deleted
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- 947
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What happens if I run a VM while copying the qcow2 file / can I backup by copying the VM file while running?
I'm trying to understand how the write happens with a VM. It looks like running one is not blocked while copying it for a backup. Will the copy contain any modified files like the boot log? Or will it ...
- 797
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qemu-img command doesn't create the qcow2 file
I am using a macOS 12.2.1 with m1 chip. I successfully installed qemu using brew. I am trying to convert my ubuntu iso file to qcow2. When I run,
qemu-img create -f qcow2 ubuntu-20.04.3-live-server-...
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When is a disk sync necessary on qcow2?
I'm running Apache on a VM with a qcow2 disk. Apache runs a (compiled C++) program which does the following:
It calls system to run another (C++) program which creates a file
It then attempts to ...
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Can qemu-img uncompress qcow2 file?
We can use the -c option for qemu-img to compress the qcow2 file, e.g., here, but at the cost of uncompressing it while using. Suppose I am given a compressed qcow2 file, does qemu-img have any option ...
- 155
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Get a raw disk image from qcow2 [duplicate]
I want to install Ubuntu (or any distro) as UEFI with QEMU/libvirt and make some changes there at runtime and shut down the machine. This will create a qcow2 disk.
If this was not a virtual machine ...
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