Seems that the command:
dracut --regenerate-all --force
caused the grub boot menu (where one can select a kernel, etc.) to disappear. How would I get the grub menu on boot back again?
EDIT: since i am UEFI- the command:
grub2-mkconfig -o /boot/efi/EFI/rocky/grub.cfg
brought the grub menu back.
Please let me know if this is needed (for any reason; as it was needed with Centos 7.9):
echo ‘add_drivers+=" nvme "’ > /etc/dracut.conf.d/nvme.conf
Thank you.