docs: add guidance about resolv.conf - #2450
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cgwalters
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Sep 10, 2026
Users keep copying the /etc/resolv.conf they see during a container build into the image, or hitting a dangling resolver symlink after install, because the file a container runtime bind-mounts during `RUN` is not the booted host's configuration. Document the one thing bootc does about it -- removing a zero-length /etc/resolv.conf and /etc/hostname left by the runtime at import -- and point at the network stack (NetworkManager, systemd-resolved) for everything else, including static DNS. If a file really has to ship in the image, keep /etc/resolv.conf a tmpfiles.d symlink to content under /usr, since a regular file in /etc sticks across upgrades. Assisted-by: AI Signed-off-by: Joseph Marrero Corchado <jmarrero@redhat.com>
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I got Claude Code with Fable 5.1 to also verify each example by creating containers and verifying with BCVK. |
cgwalters
approved these changes
Sep 14, 2026
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| For Fedora-derived images, removing the `systemd-resolved` package is generally | ||
| clearer than only disabling its service: the package also owns the tmpfiles | ||
| rule that creates the symlink. Do the removal in a `RUN --network=none` step: |
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Yeah though at some point it's cleaner to do a "from scratch" style build for this stuff.
cgwalters
enabled auto-merge (rebase)
September 14, 2026 18:39
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Users keep copying the /etc/resolv.conf they see during a container
build into the image, or hitting a dangling resolver symlink after
install, because the file a container runtime bind-mounts during
RUNis not the booted host's configuration. Document the one thingbootc does about it -- removing a zero-length /etc/resolv.conf and
/etc/hostname left by the runtime at import -- and point at the
network stack (NetworkManager, systemd-resolved) for everything else,
including static DNS. If a file really has to ship in the image, keep
/etc/resolv.conf a tmpfiles.d symlink to content under /usr, since a
regular file in /etc sticks across upgrades.