boot=/dev/sda
root=/dev/sda1
map=/boot/map

lba32

prompt
timeout=50

default=linux

image=/boot/vmlinuz-5.10.46-r740
    label=Linux
    read-only
    append="rootfstype=ext4 net.ifnames=0 loglevel=4 console=tty0 2"

image=/boot/vmlinuz-4.19.0-17-amd64
    label=4.19.0-17-amd64
    initrd=/boot/initrd.img-4.19.0-17-amd64
    read-only
    append="rootfstype=ext4 net.ifnames=0 loglevel=4 console=tty0 2"