bcvk requires sshd enabled in container image to be able to install into a disk image #236

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1. cgwalters commented on Mar 30, 2026

   

   cgwalters

   on Mar 30, 2026

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   Likely systemd.wants=sshd.service.

   Yeah makes sense.

   That said I think bigger picture we should get away from the ssh requirement anyways. Annoying thing here is systemd.extra-unit* aren't in RHEL9. I did some PoC patches to backfill that into the target initramfs. Once we have that it's easy to execute arbitrary code.
2. prestist commented on Nov 5, 2026

   

   prestist

   on Nov 5, 2026

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   One more requirement for minimal images: sshd by itself is not sufficient.

   I reproduced this with a very minimal bootc image (systemd, kernel, dnf, bootc, no sshd).

   After adding openssh-server and openssh-clients, sshd came up and was listening:

   sshd.service: Server listening on 0.0.0.0 port 22.
   

   but bcvk still failed with Timeout waiting for readiness after 240s. The guest journal showed the interface came up as enp0s7 but there was no DHCP activity at all, because the image has no NetworkManager and no dhcp-client. qemu's hostfwd=tcp::2222-:22 accepted the connection and then hung at banner exchange, since the guest had no address.

   Once I added NetworkManager, readiness was achieved:

   dhcp4 (enp0s7): state changed new lease, address=10.0.2.15
   

   So the requirement is sshd plus a DHCP-capable network stack (NetworkManager, or systemd-networkd with DHCP enabled), plus the ssh client in the image, since bcvk execs ssh inside the ephemeral container.

   Separately, to-disk also needs --filesystem on images without a bootc install config:

   error: Installing to disk: Creating rootfs: No install configuration found, and no filesystem specified
   

   With all of that, both to-disk and libvirt run succeed on the minimal image.

   Assisted by AI tooling.