mkosi tools configuration does not recieve Snapshot=

[chovanecadam]

mkosi commit the issue has been seen with

f9948b5 - current main

Used host distribution

Arch

Used target distribution

Arch

Linux kernel version used

No response

CPU architectures issue was seen on

None

Unexpected behaviour you saw

When Mirror=https://archive.archlinux.org is set in mkosi.conf, the tools image receives this configuration. However, it doesn't receive the Snapshot=2026/02/22 option. The resulting URL in pacman.conf is wrong and results in 404 errors:

• wrong: https://archive.archlinux.org/$repo/os/$arch
• expected: https://archive.archlinux.org/repos/2026/02/22/$repo/os/$arch

mkosi should pass both Mirror= and Snapshot= settings to mkosi.tools. Alternatively, it shouldn't pass Mirror= at all and require setting ToolsTreeMirror= explicitely.

Used mkosi config

[Distribution]
Distribution=arch
Architecture=x86-64
Mirror=https://archive.archlinux.org
Snapshot=2026/02/22

[Build]
ToolsTree=default

mkosi output

‣ Loading configuration file /home/me/code/mkosi/a/mkosi.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.conf.d/arch.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.profiles/misc/mkosi.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.profiles/misc/mkosi.conf.d/arch.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.profiles/package-manager/mkosi.conf.d/arch.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.profiles/runtime/mkosi.conf
‣ Loading configuration file /tmp/tmp4o2dculs/resources/mkosi-tools/mkosi.profiles/runtime/mkosi.conf.d/arch.conf
‣ /home/me/code/mkosi/a/mkosi.tools does not exist, not reusing cached images
‣ /home/me/code/mkosi/a/mkosi.tools does not exist, not reusing cached images
‣ /home/me/code/mkosi/a/mkosi.tools does not exist, not reusing cached images
‣ Syncing package manager metadata
‣ + pacman --root=/buildroot --logfile=/dev/null --dbpath=/var/lib/pacman --cachedir=/var/cache/pacman/mkosi --cachedir=/var/cache/pacman/pkg --hookdir=/buildroot/etc/pacman.d/hooks --arch x86_64 --color auto --noconfirm --sync --refresh
:: Synchronizing package databases...
 core.db failed to download
 extra.db failed to download
error: failed retrieving file 'core.db' from archive.archlinux.org : The requested URL returned error: 404
error: failed retrieving file 'extra.db' from archive.archlinux.org : The requested URL returned error: 404
error: failed to synchronize all databases (failed to retrieve some files)
‣ "pacman --root=/buildroot --logfile=/dev/null --dbpath=/var/lib/pacman --cachedir=/var/cache/pacman/mkosi --cachedir=/var/cache/pacman/pkg --hookdir=/buildroot/etc/pacman.d/hooks --arch x86_64 --color auto --noconfirm --sync --refresh" returned non-zero exit code 1.
‣ Sandbox command: mkosi-sandbox --bind /proc /proc --unsetenv TMPDIR --setenv SYSTEMD_OFFLINE 1 --ro-bind /usr /usr --ro-bind /opt /opt --symlink usr/bin /bin --symlink usr/bin /sbin --symlink usr/lib /lib --symlink usr/lib /lib64 --dir /var/tmp --dir /var/log --unshare-ipc --ro-bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/tmp/tmpz098up5n/mkosi/sandbox.py /sandbox.py --dev /dev --ro-bind /etc/ld.so.cache /etc/ld.so.cache --ro-bind /run/systemd/resolve /run/systemd/resolve --ro-bind /etc/resolv.conf /etc/resolv.conf --setenv PATH /usr/bin:/usr/sbin --ro-bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/sandbox/etc /etc --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/tmp/mkosi-var-tmp-f71054bba5e145f8 /srv --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/tmp/mkosi-var-tmp-dcbeeb3ff3334d51 /media --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/tmp/mkosi-var-tmp-2a396dad209545c7 /mnt --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/tmp/mkosi-var-tmp-547efbc0ecc74135 /var --dir /run --dir /tmp --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/tmp/mkosi-var-tmp-a2001841893d4e28 /var/tmp --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/root /buildroot --ro-bind /etc/ca-certificates /etc/ca-certificates --ro-bind /etc/ssl /etc/ssl --bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/repository /repository --bind /home/me/.cache/mkosi/mkosi-metadata-sp_10top/lib/pacman/sync /var/lib/pacman/sync --bind /home/me/.cache/mkosi/mkosi-metadata-sp_10top/cache/pacman /var/cache/pacman --bind '/home/me/.cache/mkosi/arch~rolling~x86-64/cache/pacman/pkg' /var/cache/pacman/pkg --ro-bind /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/repository /var/cache/pacman/mkosi --bind +/buildroot/var/lib/pacman/local /var/lib/pacman/local --become-root --suppress-chown --suppress-sync --ro-bind-try /home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/root/etc/machine-id /buildroot/etc/machine-id --dir /run/user/0 --ro-bind /etc/ssl/certs/ca-certificates.crt /proxy.cacert
‣ + rm -rf -- /work/home/me/.cache/mkosi/mkosi-workspace-v9m46oqu /work/home/me/.cache/mkosi/mkosi-workspace-v9m46oqu/root
‣ + tput cnorm
‣ + tput smam
Traceback (most recent call last):
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/run.py", line 104, in uncaught_exception_handler
    yield
  File "/home/me/.local/share/uv/python/cpython-3.12.7-linux-x86_64-gnu/lib/python3.12/contextlib.py", line 81, in inner
    return func(*args, **kwds)
           ^^^^^^^^^^^^^^^^^^^
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/__main__.py", line 44, in main
    run_verb(args, tools, images, resources=resources)
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/__init__.py", line 5109, in run_verb
    tkd, tmd = sync_repository_metadata(
               ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/__init__.py", line 4906, in sync_repository_metadata
    context.config.distribution.installer.package_manager(context.config).sync(
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/installer/pacman.py", line 259, in sync
    cls.invoke(context, "--sync", ["--refresh", *(["--refresh"] if force else [])])
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/installer/pacman.py", line 189, in invoke
    return run(
           ^^^^
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/run.py", line 243, in run
    with spawn(
         ^^^^^^
  File "/home/me/.local/share/uv/python/cpython-3.12.7-linux-x86_64-gnu/lib/python3.12/contextlib.py", line 144, in __exit__
    next(self.gen)
  File "/tmp/.tmpeQVdsz/archive-v0/yzLhL8Zfaqj-efUTUtjs8/lib/python3.12/site-packages/mkosi/run.py", line 413, in spawn
    raise subprocess.CalledProcessError(returncode, cmdline)
subprocess.CalledProcessError: Command '['pacman', '--root=/buildroot', '--logfile=/dev/null', '--dbpath=/var/lib/pacman', '--cachedir=/var/cache/pacman/mkosi', '--cachedir=/var/cache/pacman/pkg', '--hookdir=/buildroot/etc/pacman.d/hooks', '--arch', 'x86_64', '--color', 'auto', '--noconfirm', '--sync', '--refresh']' returned non-zero exit status 1.

[chovanecadam]

mkosi summary output with the configuration above:

IMAGE: tools

    CONFIG:
                           Profiles: misc
                                     package-manager
                                     runtime
                       Dependencies: none
                    Minimum Version: none
                  Configure Scripts: none
                   Pass Environment: none

    DISTRIBUTION:
                       Distribution: arch
                            Release: rolling
                       Architecture: x86-64
                             Mirror: https://archive.archlinux.org
                           Snapshot: none

running mkosi build -f --debug --debug-shell:

‣ Loading configuration file /home/me/code/mkosi/a/mkosi.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.conf.d/arch.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.profiles/misc/mkosi.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.profiles/misc/mkosi.conf.d/arch.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.profiles/package-manager/mkosi.conf.d/arch.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.profiles/runtime/mkosi.conf
‣ Loading configuration file /tmp/tmpczgpf_0t/resources/mkosi-tools/mkosi.profiles/runtime/mkosi.conf.d/arch.conf
‣ /home/me/code/mkosi/a/mkosi.tools does not exist, not reusing cached images
‣ /home/me/code/mkosi/a/mkosi.tools does not exist, not reusing cached images
‣ /home/me/code/mkosi/a/mkosi.tools does not exist, not reusing cached images
‣ Populating pacman keyring
‣ + pacman-key --init
gpg: /etc/pacman.d/gnupg/trustdb.gpg: trustdb created
gpg: no ultimately trusted keys found
gpg: starting migration from earlier GnuPG versions
gpg: porting secret keys from '/etc/pacman.d/gnupg/secring.gpg' to gpg-agent
gpg: migration succeeded
==> Generating pacman master key. This may take some time.
gpg: Generating pacman keyring master key...
gpg: directory '/etc/pacman.d/gnupg/openpgp-revocs.d' created
gpg: revocation certificate stored as '/etc/pacman.d/gnupg/openpgp-revocs.d/F6C79B4330E2C16223CB986C1F6E8DC0EBC9260C.rev'
gpg: Done
==> Updating trust database...
gpg: marginals needed: 3  completes needed: 1  trust model: pgp
gpg: depth: 0  valid:   1  signed:   0  trust: 0-, 0q, 0n, 0m, 0f, 1u
‣ + pacman-key --populate
==> Appending keys from archlinux.gpg...
==> Locally signing trusted keys in keyring...
  -> Locally signed 5 keys.
==> Importing owner trust values...
gpg: setting ownertrust to 4
gpg: setting ownertrust to 4
gpg: setting ownertrust to 4
gpg: inserting ownertrust of 4
gpg: setting ownertrust to 4
==> Disabling revoked keys in keyring...
  -> Disabled 36 keys.
==> Updating trust database...
gpg: Note: third-party key signatures using the SHA1 algorithm are rejected
gpg: (use option "--allow-weak-key-signatures" to override)
gpg: marginals needed: 3  completes needed: 1  trust model: pgp
gpg: depth: 0  valid:   1  signed:   5  trust: 0-, 0q, 0n, 0m, 0f, 1u
gpg: depth: 1  valid:   5  signed:  85  trust: 0-, 0q, 0n, 5m, 0f, 0u
gpg: depth: 2  valid:  72  signed:  19  trust: 72-, 0q, 0n, 0m, 0f, 0u
gpg: next trustdb check due at 2026-03-13
‣ Syncing package manager metadata
‣ + pacman --root=/buildroot --logfile=/dev/null --dbpath=/var/lib/pacman --cachedir=/var/cache/pacman/mkosi --cachedir=/var/cache/pacman/pkg --hookdir=/buildroot/etc/pacman.d/hooks --arch x86_64 --color auto --noconfirm --sync --refresh
:: Synchronizing package databases...
 core.db failed to download
 extra.db failed to download
error: failed retrieving file 'core.db' from archive.archlinux.org : The requested URL returned error: 404
error: failed retrieving file 'extra.db' from archive.archlinux.org : The requested URL returned error: 404
error: failed to synchronize all databases (failed to retrieve some files)
‣ "mkosi-sandbox --proc /proc --unsetenv TMPDIR --setenv SYSTEMD_OFFLINE 1 --ro-bind /usr /usr --ro-bind /opt /opt --symlink usr/bin /bin --symlink usr/bin /sbin --symlink usr/lib /lib --symlink usr/lib /lib64 --dir /var/tmp --dir /var/log --unshare-ipc --ro-bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/tmp/tmpxbpukf2_/mkosi/sandbox.py /sandbox.py --dev /dev --ro-bind /etc/ld.so.cache /etc/ld.so.cache --ro-bind /run/systemd/resolve /run/systemd/resolve --ro-bind /etc/resolv.conf /etc/resolv.conf --setenv PATH /usr/bin:/usr/sbin --ro-bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/sandbox/etc /etc --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/tmp/mkosi-var-tmp-083900ca1b124438 /srv --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/tmp/mkosi-var-tmp-91f898d48b5c4112 /media --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/tmp/mkosi-var-tmp-4f359feef47d44d0 /mnt --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/tmp/mkosi-var-tmp-c9afb699060c4745 /var --dir /run --dir /tmp --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/tmp/mkosi-var-tmp-4295ca34b1c34511 /var/tmp --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/root /buildroot --ro-bind /etc/ca-certificates /etc/ca-certificates --ro-bind /etc/ssl /etc/ssl --bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/repository /repository --bind /home/me/.cache/mkosi/mkosi-metadata-lsqzej1w/lib/pacman/sync /var/lib/pacman/sync --bind /home/me/.cache/mkosi/mkosi-metadata-lsqzej1w/cache/pacman /var/cache/pacman --bind '/home/me/.cache/mkosi/arch~rolling~x86-64/cache/pacman/pkg' /var/cache/pacman/pkg --ro-bind /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/repository /var/cache/pacman/mkosi --ro-bind /home/me/.cache/mkosi/mkosi-keyring-0g9vtnjn /etc/pacman.d/gnupg --bind +/buildroot/var/lib/pacman/local /var/lib/pacman/local --become-root --suppress-chown --suppress-sync --ro-bind-try /home/me/.cache/mkosi/mkosi-workspace-_o5ekzri/root/etc/machine-id /buildroot/etc/machine-id --dir /run/user/0 --ro-bind /etc/ssl/certs/ca-certificates.crt /proxy.cacert pacman --root=/buildroot --logfile=/dev/null --dbpath=/var/lib/pacman --cachedir=/var/cache/pacman/mkosi --cachedir=/var/cache/pacman/pkg --hookdir=/buildroot/etc/pacman.d/hooks --arch x86_64 --color auto --noconfirm --sync --refresh" returned non-zero exit code 1.
bash-5.3# cat /etc/pacman.conf
[options]
SigLevel = Required DatabaseOptional
LocalFileSigLevel = Optional
ParallelDownloads = 5
Architecture = x86_64

Include = /etc/mkosi-local.conf

[core]
Server = https://archive.archlinux.org/$repo/os/$arch

[extra]
Server = https://archive.archlinux.org/$repo/os/$arch

[chovanecadam]

A few workarounds:

• don't set Mirror, only use Snapshot in mkosi.conf, or
• also set ToolsTreeMirror in mkosi.conf, or
• set Snapshot in mkosi.tools.conf.