How to install QEMU on OSX and install an Ubuntu VM

qemu_ubuntu.md

Install QEMU on OSX

QEMU requires brew in OSX, so we need to install brew first.

Installing Brew

To install brew we need to have the developer tools enabled in our system. In order to install those tools, we have two options.

1. Download Xcode form the AppStore
2. In your terminal run the following command: xcode-select --install

Once you have the developer tools, run the following command in your terminal to install brew:

$ ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Once the installation is finished, we can test the brew installation in our terminal with the command

$ brew doctor

Installing QEMU

Now that we have brew on the system we can proceed to the QEMU installation. To do that we use a simple command:

$ brew install qemu

When the installation is finished, we can run the following command to test if the installation was successful:

$ qemu-system-x86_64 --version

Installing Ubuntu on QEMU

We need to follow a series of steps in order to install an Ubuntu VM on QEMU. The first one is go to the Ubuntu website and download an .iso file of the operating system. Once we have the .iso, we need to to this:

1. Create a folder in your computer (with any name and anywhere). $ mkdir ubuntu_vm
2. Move the .iso file in the folder that you just create. $ mv ubuntu.iso ./your-folder
3. Then move inside the folder you just create $ cd ubuntu_vm
4. Inside the folder, create the drive file of the system qemu-img create -f qcow2 ubuntu_drive.qcow2 10G
5. Run ls to verify that the .iso and the qcow file are inside the folder

Once you have the previous steps, you can run the following command to run the iso and complete the installation:

qemu-system-x86_64 \
  -m 2048 \
  -vga virtio \
  -show-cursor \
  -usb \
  -device usb-tablet \
  -enable-kvm \
  -cdrom your_ubuntu.iso
  -drive file=ubuntu_drive.qcow2,if=virtio \
  -accel hvf \
  -cpu host

The previous command, will run the iso, when you are there, you need to complete the ubuntu installation, so once you see something you must:

1. Click on Install Ubuntu
2. Select erase disk when the installer ask about it
3. When the installer asks you to restart the machine close the QEMU window.

Now, in order to make more easy to run our QEMU VM, we are going to create a shell command. So, lets do the following.

First, create a new file in any place you want:

$ vi ubuntuvm.sh

Then, paste the following and adept it to your needs:

qemu-system-x86_64 \
  -m 2048 \
  -vga virtio \
  -show-cursor \
  -usb \
  -device usb-tablet \
  -enable-kvm \
  -cdrom your_ubuntu.iso
  -drive file=~/absolute/path/to/your/ubuntu_drive.qcow2,if=virtio \
  -accel hvf \
  -cpu host

And finally, write and quit.

As you can see, the command deletes the instruction about the .iso file. This is because now we have the operating system already installed. Now in order to run the vm, we need to make our file executable. So run the following command:

$ chmod +x ubuntuvm.sh

And finally to run it:

$ ./ubuntuvm

And that is it. We should see our virtual machine running correctly.

The given command to launch ubuntu iso unfortunately did not work for me (MaxOS 10.15 QEMU 7.0). I had to to something like this:

qemu-system-x86_64
-machine type=q35,accel=hvf
-smp 2 -hda ubuntu_drive.qcow2
-cdrom xubuntu-22.04-desktop-amd64.iso
-m 4G
-vga virtio
-usb
-device usb-tablet
-display default,show-cursor=on

I'm on MacOS X 12.4, the command I used was
qemu-system-x86_64 -m 2048 -vga virtio -usb -device usb-tablet -cdrom ubuntu.iso -drive file=u-disk.qcow2,if=virtio -accel hvf -cpu host

Since the MacBook I'm using is from 2015, the emulation is still very slow, and I probably won't go through with the install. QEMU newbie here: I'm not sure if another command would make it run any faster.

I'm on Mojave, and Homebrew has decided that my OS is too old and I can't use it anymore. Any alternatives? Macports fails trying to install Spice Server.