# Using qemu without a gui {#Using_qemu_without_a_gui}

## Enable Virtualization in your PC UEFI/BIOS. {#Enable_Virtualization_in_your_PC_UEFI_47BIOS.}

In order to use -enable-kvm option (see below at qemu invokation)
we may need to enable hardware virtualization.
*(help needed to clarify the validity of that assertion)*

Hardware virtualization feature is disabled by default
on AMD and Intel CPU's. So you will have to enable them
manually if you do wish to use it. Otherwise QEMU will be very slow.

If you have Intel CPU, then all you have to do is, enable
VT-x or VT-d from the BIOS of your motherboard.

For AMD CPU, you have to enable AMD-v from the BIOS of
your motherboard.

If your CPU supports hardware virtualization, and you
enabled it from the BIOS of your computer, then you can
check whether Virtualization is enabled :

\$ lscpu \| grep Virt
or
\$ egrep \--color=auto \'vmx\|svm\|0xc0f\' /proc/cpuinfo

## Installation in Daedalus {#Installation_in_Daedalus}

### related packages {#related_packages}

I list qemu packages that emulate some known cpu architectures:

- qemu-system-x86
  - /usr/bin/kvm
  - /usr/bin/qemu-system-amd64
  - /usr/bin/qemu-system-i386
  - /usr/bin/qemu-system-x86_64
- qemu-system-arm
  - /usr/bin/qemu-system-arm
- qemu-system-misc
  - /usr/bin/qemu-system-riscv32
  - /usr/bin/qemu-system-riscv64

For each of these binaries we can get a more detailed list
of supported cpus and various boards,systems build around that cpu:

    $ qemu-system-x86_64 -machine help
    pc                   Standard PC (i440FX + PIIX, 1996) (alias of pc-i440fx-7.2)
    pc-i440fx-7.2        Standard PC (i440FX + PIIX, 1996) (default)
    q35                  Standard PC (Q35 + ICH9, 2009) (alias of pc-q35-7.2)
    pc-q35-7.2           Standard PC (Q35 + ICH9, 2009)

    $ qemu-system-x86_64 -cpu help
    x86 486                   (alias configured by machine type)
    x86 486-v1
    x86 pentium               (alias configured by machine type)
    x86 pentium-v1
    x86 coreduo               (alias configured by machine type)
    x86 coreduo-v1            Genuine Intel(R) CPU           T2600  @ 2.16GHz
    x86 phenom                (alias configured by machine type)
    x86 phenom-v1             AMD Phenom(tm) 9550 Quad-Core Processor


    $ qemu-system-riscv64 -machine help
    Supported machines are:
    microchip-icicle-kit Microchip PolarFire SoC Icicle Kit
    none                 empty machine
    shakti_c             RISC-V Board compatible with Shakti SDK
    sifive_e             RISC-V Board compatible with SiFive E SDK
    sifive_u             RISC-V Board compatible with SiFive U SDK

    $ qemu-system-riscv64 -cpu help
    any
    rv64
    shakti-c
    sifive-e51
    sifive-u54
    x-rv128


    $ qemu-system-arm -machine help
    cubieboard           cubietech cubieboard (Cortex-A8)
    microbit             BBC micro:bit (Cortex-M0)
    raspi2b              Raspberry Pi 2B (revision 1.1)


    $ qemu-system-arm -cpu help
      arm946
      cortex-a15
      cortex-a7

## creating our first virtual devuan machine with two commands ! {#creating_our_first_virtual_devuan_machine_with_two_commands_33}

Prerequisites:

- qemu-system-x86 installed
- net iso installation medium of devuan stable downloaded.

``` bash
$ cd myvirtualmachines
# creating our virtual disk
$ qemu-img create -f qcow2 devuanstable.qcow2 16G
#  creating our vm
$ qemu-system-x86_64 -enable-kvm -m 2048 -nic user,model=virtio \
       -drive file=devuanstable.qcow2,media=disk,if=virtio \
       -cdrom devuan_daedalus_5.0.1_amd64_netinstall.iso
#  starging our vm  
$ qemu-system-x86_64 -enable-kvm -m 2048 -nic user,model=virtio -drive file=devuanstable.qcow2,media=disk,if=virtio
```

When invoking qemu to start our vm we must at least provide :

- -enable-kvm / or the emulation would be vary slow
- -m 2048 / the default (128MiB) may crash the program.

Due to default values we can run our emulated x86_64 system with:

    $ qemu-system-x86_64 -enable-kvm -m 2048 devuanstable.qcow2