guestfs-release-notes - libguestfs Release Notes


The big news in this release is that the virt tools like virt-builder(1), virt-cat(1), virt-customize(1), virt-df(1), and many more were moved to a new project. The temporary repository for the new guestfs-tools project is here: while we set up a permanent home for it on gitlab. The tarballs containing the tools are here:

Spinning out all of the tools into a new repository has made libguestfs a bit easier and simpler to build and manage, and allows us to focus on just being the API.

Note that the tools guestfish(1) (which is really a "shell API"), guestmount(1), libguestfs-test-tool(1) and virt-rescue(1) are still part of the libguestfs repo.

The not quite so big news is that we have moved away from FreeNode to Libera Chat for IRC. The new channel on Libera is called #guestfs (thanks Daniel Berrangé).

Language bindings

Libguestfs is now compatible with Go 1.16, and defines a Go module (thanks Gianfranco Costamagna).

Memory leaks in Python APIs that returned structs are fixed (thanks 朱丹).

Python PyPi code has been relicensed to LGPLv2+ (from GPLv2+).


Inspection of RPM guests now uses librpm instead of trying to parse the Berkeley DB directly. Since most RPM-based guests have replaced BDB with sqlite this allows us to read these newer guests while retaining compatibility with the older guests (thanks Panu Matilainen).

Inspection of RHEL 8+ with split /usr configuration has been made more reliable.

Inspection of Windows Server 2022 should now work correctly (Yongkui Guo).


New APIs

No new APIs were added in libguestfs 1.46.

Other API changes

The output of the guestfs_cap_get_file API has changed slightly because of changes in the underlying libcap. This isn't strictly speaking an API break because the new output is a still valid but more compact description of file capabilities, but because it is different it may cause problems for users of the API.

The guestfs_mkfs_btrfs API now ignores the allocstart parameter since it was deprecated by btrfs 4.14.1 and later removed.

guestfs_isoinfo_* APIs now directly parse the CD Primary Volume Descriptor instead of using an external tool. The APIs should appear to work exactly the same (thanks Thomas Schmitt).

You can now force the appliance to use KVM or fail if not supported (Sam Eiderman).

Because of a change to XFS in version 5, disabling lazy-counters no longer works. The API still works for earlier versions of XFS (Laszlo Ersek).

Build changes

The build now uses and requires PCRE2 (instead of PCRE).

This version requires libvirt ≥ 7.1.0, if libvirt is enabled.

gnulib is no longer bundled with libguestfs, making builds from git much simpler.

Perl Sys::Virt (libvirt bindings for Perl) are no longer required by libguestfs.

The code has been compiled with both LTO and GCC -fanalyzer and many bugs and warnings fixed.

Allow projects like guestfs-tools and virt-v2v to be compiled with locally built (but not installed) libguestfs (Laszlo Ersek).

Tests now run in parallel (many additional fixes by Laszlo Ersek).

Work around RAID0 regression in Linux 3.14/5.4 (Laszlo Ersek).

Support for RISC-V (Heinrich Schuchardt).

Support for building on Alma and Cloud Linux (Александр Кравченко).

Fix to compile with OCaml 4.12.

The tarball no longer includes the ChangeLog file. To get a detailed changelog, please look at the upstream git repository.

Don't assume bash in the ./configure script (Martin Kletzander).

Fix ./configure --with-distro option (Alexandre Iooss).

Various fixes for qemu 6.1.

Fix creating appliance dependencies on Debian (Hilko Bengen).

Update appliance packages on SUSE and several other improvements to the init script (Olaf Hering).


We now use the qemu / libvirt feature -cpu max to select the best CPU to run the appliance. This should improve performance for things like encrypted disks (Daniel Berrangé).

When passing the appliance filesystem UUID to supermin we now read it directly out of the appliance instead of using the file(1) program. This is more reliable, especially as file often breaks or changed its output.

The qemu -enable-fips option is no longer used. It was not needed and has been deprecated by qemu.

On Fedora, pull in glibc-gconv-extra to fix the guestfs_syslinux API (Yongkui Guo).

We no longer use qemu's sga (Serial Graphics Adapter) option ROM, instead using the equivalent seabios feature.

Bugs fixed

Use -machine graphics=off instead of sga device

[RFE] libguestfs: Add detection of AlmaLinux and CloudLinux

osinfo is not correct when handling windows server 2022 image

syslinux: failed to create ldlinux.sys

The lstatns function has a memory leak. (python3)

[Regression] ls: cannot read symbolic link after running guestmount

virt-v2v: error: inspection could not detect the source guest (or physical machine)

Move libguestfs from PCRE to PCRE2

[Regression] lvcreate fails to wipe signatures again

Virt-v2v can't convert rhel8 guest whose usr partition is independent

libguestfs-1.44.0 - guestfs appliance path broken

virt-builder + virt-install creates a VM that cannot boot fedora 33

libguestfs assumes rpmdb is in Berkeley DB format

[Debian] Missing db_dump abort inspection


guestfs-examples(1), guestfs-faq(1), guestfs-performance(1), guestfs-recipes(1), guestfs-testing(1), guestfs(3), guestfish(1),


Alexandre Iooss
Daniel P. Berrangé
Heinrich Schuchardt
Hilko Bengen
Laszlo Ersek
Martin Kletzander
Remi Collet
Richard W.M. Jones
Sam Eiderman


Copyright (C) 2009-2021 Red Hat Inc.


This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.


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