Comment # 4 on bug 1023618 from Josef Reidinger

(In reply to Frans Leerink from comment #3)
> Yesterday evening I updated the tumbleweed system (approx 500 updates) and
> shut the system down as soon as the system reported that the updates are
> installed successfully.
> 
> This morning again all other boot options,like windows 7 and opensuse-Leap,
> are not available in boot menu. This happens regularly, but not always,
> after an update.
> 
> I have corrected this situation by running Yast/system/bootloader without
> any new input.

to debug this we need output of "save_y2logs" so we can check what happen and
what is your configuration.