play-with-coreos

This project is created to build, run and test CoreOS. It's just for learning.
It's tested on Centos8, and Fedora32. Not recommend for Ubuntu Distribution since SELinux is used.

A demo of the start and destroy of a CoreOS VM can be found here: README.md Demo section.

• Prerequisites
• Hardware Requirements
• Quickstart
  • Run CoreOS with ignition
  • CoreOS Assembler
• Usage
• Troubleshooting
• Demo
  • CoreOS Assembler Build FCOS
  • Start FCOS qcow2 VM
  • Running etcd container
  • Destroy VM

Prerequisites

• make
• virt-install
• Container Runtime: Podman or Docker
• libvirt
• SELinux: Enforcing

Hardware Requirements

• Virtualization Support

$ egrep '^flags.*(vmx|svm)' /proc/cpuinfo

If this command resuls in nothing printed, your system does not support the relevant virtualization extensions. You can still use QEMU/KVM, but the emulator will fall back to software virtualization, which is much slower. (--virt-type=qemu)

• KVM kernel module To verify that the KVM kernel modules are properly loaded:

$ lsmod | grep kvm

If this command lists kvm_intel or kvm_amd, KVM is properly configured.

Quickstart

Run CoreOS with ignition

To start with the defaults, run the following:

$ make run

To start with customized variables:

$ NAME=vm-1 CPU=4 MEMORY=4096 DISK=2 IMAGE=/path/to/imgage YAML=/path/to/ignition.yaml make run

To Destroy:

$ make destroy

CoreOS Assembler

To build coreOS with defaults (https://github.com/coreos/fedora-coreos-config)

$ make cosa-build

To build custom coreOS

$ COSA_DIR=/path/to/working-dir CONFIG_REPO=<url> make cosa-build

To Clean up COSA working directory

$ make cosa-clean

Usage

Run make help to see available commands.

Usage: make [TARGET ...]

check-cont-runt                To check which container runtime is used
check-virt                     To check whether system has a CPU with virtualization support
clean                          Remove Ignition files
cosa-build                     CoreOS Assembler - Build coreos
cosa-clean                     CoreOS Assembler - Clean coreos confiuration directory
cosa-fetch                     CoreOS Assembler - Fetch metadata and packages
cosa-init                      CoreOS Assembler - Initialize configuration repo
cosa-run                       CoreOS Assembler - Run built coreos
destroy                        Destroy VM
download-fcos-iso              Download Fedora CoreOS ISO image
download-fcos-pxe              Download Fedora CoreOS PXE kernel
download-fcos-qcow2            Download Fedora CoreOS qcow2 image
fcos-qcow2-autologin           Create Fedora CoreOS from qcow2 image - test autologin
fcos-qcow2-container           Create Fedora CoreOS from qcow2 image - test create container
fcos-qcow2-service             Create Fedora CoreOS from qcow2 image - test systemd service
help                           Show this help menu.
list                           List of Virtual Machines created by virsh-install
prerequisite                   Run check prerequisite
pull-all                       Pull all required images
pull-coreos-installer          Pull coreor-installer image
pull-cosa                      Pull coreos-assembler image
pull-fcct                      Pull fcct (Fedora CoreOS Config Transpiler) image
pull-ignition                  Pull Ignition image
run                            Create and Run CoreOS VM
status                         Status of Virtual Machines created by virsh-install
validate-ign                   Verifying Ignition config format is valid
yml2ign                        Convert configuation YAML file to IGN file

[Note] To escape out of the serial console, press CTRL + ]

Troubleshooting

ioctl(KVM_CREATE_VM) failed: 16 Device or resource busy

This is caused by the virtualization technology is being locked by another hypervisor (ex: VirtualBox). To solved this problem, we just turn off running VirtualBox instance or run virt-install with option --virt-type=qemu. If closing VirtualBox doesn't fix it, you can stop the driver service with sudo systemctl stop vboxdrv.

Demo

CoreOS Assembler Build FCOS

Start FCOS qcow2 VM

Running etcd container

Destroy VM