Fabian Lee : Software Engineer

Docker: building multi-platform images that use fat manifest list/index

September 16, 2023
Categories: Containers, Development

Docker can build multi-platform images that use a manifest index (fat manifest list) by using the Docker buildx command with backing containerd runtime and QEMU for cross-platform emulation. Using a manifest index for multi-platform images simplifies application level orchestration by using the same name and version for all architectures. For example: # same image name … Docker: building multi-platform images that use fat manifest list/index

Docker: QEMU emulation to run arm64 images from native amd64 host

September 15, 2023
Categories: Containers, Virtualization

If you want to use Docker to build cross-platform images, the first step is to enable QEMU to run images targeted at others architectures via emulation. I assume you have installed Docker CE and its containerd runtime as described here, and are running on a x86_64 host.

KVM: creating and reverting libvirt external snapshots

January 10, 2021
Categories: Linux, Virtualization

Update July 2021: I have seen errors with external snapshots of volumes on versions of QEMU/KVM/libvirt from Ubuntu 20 Focal. Adding note on using internal snapshot on volume backed by qcow2. Internal snapshots created on QEMU copy-on-write (qcow2) disks are the most commonly used snapshot when using libvirt. It is easy to see why; … KVM: creating and reverting libvirt external snapshots

KVM: virt-manager to connect to a remote console using qemu+ssh

February 16, 2019
Categories: Linux, Virtualization

If you are running KVM on a console-only server, you still have the option to use the graphical virt-manager. You just need to specify the method of communication (ssh, tls, tcp, etc). In this article I will show how to use virt-manager from an Ubuntu client desktop to a server running KVM and libvirtd, with … KVM: virt-manager to connect to a remote console using qemu+ssh

KVM: Implementing linked clones with a backing file

September 24, 2018
Categories: Linux

If you need KVM to bring up a full guest OS as quickly as possible, consider preparing a base disk image that can be used as the basis for any number of linked clones by using a backing file. This article is related to a previous article, “Cloning and fixing an Ubuntu host using KVM“. … KVM: Implementing linked clones with a backing file

KVM: Building the latest OVMF firmware for virtual machines

September 12, 2018
Categories: Linux

OVMF is an open-source project that implements the Unified Extensible Firmware Interface (UEFI) specification. UUEFI is designed to eventually replace the BIOS firmware interface. In this article, I will show how to build the latest OVMF image from source.

KVM: Bare metal virtualization on Ubuntu with KVM

August 27, 2018
Categories: Linux, Virtualization

Update September 2022: Validated these instructions on Ubuntu 22.04 If you are running an Ubuntu host, you have multiple choices for a virtualization hypervisor. I have written up several articles on using VirtualBox, but now let’s consider a bare metal hypervisor like KVM. KVM is a type 1 hypervisor implemented as a Linux kernel module … KVM: Bare metal virtualization on Ubuntu with KVM