Category archive for storage

An Overview of QEMU Storage Features

14 Sep 2020

This article introduces QEMU storage concepts including disk images, emulated storage controllers, block jobs, the qemu-img utility, and qemu-storage-daemon. If you are new to QEMU or want an overview of storage functionality in QEMU then this article explains how things fit together.

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Using virtio-fs on a unikernel

04 Nov 2020 — by Fotis Xenakis

This article provides an overview of virtio-fs, a novel way for sharing the host file system with guests and OSv, a specialized, lightweight operating system (unikernel) for the cloud, as well as how these two fit together.

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Presenting guest images as raw image files with FUSE

22 Aug 2021 (Updated 06 Sep 2021) — by Hanna Reitz

Sometimes, there is a VM disk image whose contents you want to manipulate without booting the VM. One way of doing this is to use libguestfs, which can boot a minimal Linux VM to provide the host with secure access to the disk’s contents. For example, guestmount allows you to mount a guest filesystem on the host, without requiring root rights.

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Introduction to Zoned Storage Emulation

17 Nov 2022 — by Sam Li

This summer I worked on adding Zoned Block Device (ZBD) support to virtio-blk as part of the Outreachy internship program. QEMU hasn’t directly supported ZBDs before so this article explains how they work and why QEMU needed to be extended.

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