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Questions tagged [qemu]

QEMU stands for "Quick EMUlator" and is a processor emulator that relies on dynamic binary translation to achieve a reasonable speed while being easy to port to new host CPU architectures.

QEMU has two operating modes:

  • User mode emulation

In this mode QEMU runs single Linux or Darwin/Mac OS X programs that were compiled for a different CPU. System calls are thunked for endianness and for 32/64 bit mismatches. Fast cross-compilation and cross-debugging are the main targets for user-mode emulation.

  • Computer emulation

In this mode QEMU emulates a full computer system, including peripherals. It can be used to provide virtual hosting of several virtual computers on a single computer. QEMU can boot many guest operating systems, including Linux, Solaris, Microsoft Windows, DOS, and BSD 1; it supports emulating several hardware platforms, including x86, x86-64, ARM, Alpha, ETRAX CRIS, MIPS, MicroBlaze, PowerPC and SPARC.

Source: wikipedia

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Difference between KVM and QEMU

I have been reading about KVM and Qemu for sometime. As of now I have a clear understanding of what they do. KVM supports hardware virtualization to provide near native performance to the Guest Operating sytems. On the other hand QEmu emulates the…
Abhishek Gupta
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free up not used space on a qcow2-image-file on kvm/qemu

we are using kvm/qemu with qcow2-images for our virtual machines. qcow2 has this nice feature where the image file only allocates the actually needed space by the virtual-machine. but how do i shrink back the image file, if the virtual machine's…
bmaeser
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Is there any way to shrink qcow2 image without converting it raw?

Is there any way to shrink qcow2 image without converting it raw? I cannot convert it to raw because I don't have disk space enough for raw image.
YOU
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Which is better image format, raw or qcow2, to use as a baseimage for other VMs?

I am using a baseimage and based on that creating many VMs. And now I want to know which is better, qcow2 or raw to use for a baseimage. Moreover, can you please tell me if there is any advantage of using this baseimage thing, instead of cloning the…
A-B
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How to start qemu directly in the console (*not* in curses or SDL)

I seem to recall being able to start qemu with only the terminal emulator output, with the graphic window disabled. And here I don't mean with the ncurses interface, that one is nice, but I want the output to flow directly into my terminal, to make…
anarcat
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KVM: Which CPU features make VMs run better?

We are using Ubuntu 12.04 with the following parameters: Dell R910 Kernel 3.2.0-25-generic #40-Ubuntu SMP x86_64 x86_64 x86_64 GNU/Linux kvm 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13 qemu-kvm 1.0+noroms-0ubuntu13 qemu-common…
PythonLearner
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understanding relationship between Qemu and KVM

What is the difference between KVM and Qemu? As I understand, latter is able to provide "user mode emulation" which means that one can run a single executable built for some other architecture like this: # file busybox-sparc busybox-sparc: ELF…
Martin
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KVM guest cannot write to 9p share owned by non-root

I am aiming to set up full write access to a 9p share for a KVM guest. Both host and guest have the same users/groups with the same IDs. Both host and guest should be able to write to the share using same usernames and I don't want to distinguish…
Greendrake
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Is there a way to determine which virtual interface belongs to a virtual machine in a kvm host?

I'm using qemu/kvm whith bridged networking. In the host machine there are several "vnetX" network interfaces without IP. I'm looking for a way to know which vnetX belong to a virtual machine. I tried to match the MAC Address values on these…
theist
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Read/write access for passthrough (9p) filesystems with libvirt/qemu?

I have recently started experimenting with the support for passthrough filesystems in recent versions of KVM/QEMU/libvirt. Making the filesystems available for read access has "just worked", but I'm a little puzzled about how write access is…
larsks
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'Unrecognised disc label' - when using parted with qemu images

I have a Linux from scratch LiveCD running on qemu vm. I'm using this command to create a hda disc for qemu: qemu-img.exe create -f qcow2 base-linux.img 5G Then I run my vm: qemu.exe -m 1024 -boot d -cdrom lfslivecd-x86-6.3-r2145.iso -hda…
Valentin V
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QEMU multiple port forwarding

I would like to forward more than one port. This command run my VM and forwards RDP port successfully: qemu-system-i386 -net nic,model=rtl8139 -net user,hostfwd=tcp::3389-:3389 -m 512M -localtime -cpu core2duo,+nx -smp 2 -usbdevice tablet -k en-us…
Anna Parker
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Solidworks: activation license mode is not supported in this virtual environment (Qemu-KVM)

The question is not around Solidworks actually, so please continue to read. The whole idea of virtualization is to be hardware independent. Before our eyes a whole new dependency level is being created - affixment to the hypervisor. As far as I know…
Michal Sokolowski
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Convert directory to QEMU/KVM virtual disk image

I have a directory filled with data at /var/backups/disk1 that I want to convert into a virtual disk image which I'll then be able to boot using QEMU or KVM (the directory contains the file system for a virtual machine, copied out via rsync). While…
Chris
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How to quit QEMU monitor?

I launched KVM VM with this command: kvm /kvm/hdd/v1/v1-1.raw -m 512 -daemonize -smp 2 -nographic -net nic,model=virtio,macaddr=aa:aa:aa:aa:aa:01 -net tap,ifname=tap0 -monitor telnet:localhost:7001,server,nowait,nodelay Then I connect to the…
artem
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