I finally came up with a workaround that can be done in a preseed.cfg (until this can be fixed properly in the kernel image)
d-i preseed/early_command string echo -e "#!/bin/sh\napt-install linux- base" > /usr/lib/post-base-installer.d/99-bug1820755; chmod +x /usr/lib /post-base-installer.d/99-bug1820755 In other words, have the early command (which runs before base- installer) set up another post-base-installer callback hook, to upgrade linux-base. Since base-installer runs its post_install_hooks between apt_update and install_kernel, this can pick up the linux-base from xenial-updates, which will let the kernel install succeed. Seems to work for me and ends up with everything at the right versions in the end. That seems better than trying to hold back the linux- image-4.4.0-143-generic, which would leave you vulnerable to USN-3910-1 . -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1820755 Title: Netboot install fails due to linux-image-4.4.0-143-generic.postinst linux-update-symlinks not found To manage notifications about this bug go to: https://bugs.launchpad.net/bluelinux/+bug/1820755/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs