(amd64)ubuntu@localhost:~$ cat /boot/grub/grub.cfg 
set default=0
set timeout=3

insmod part_gpt
insmod ext2

if [ -s $prefix/grubenv ]; then
  load_env
fi

if [ -z "$snappy_mode" ]; then
    set snappy_mode=regular
    save_env snappy_mode
fi
if [ -z "$snappy_ab" ]; then
    set snappy_ab=a
    save_env snappy_ab
fi

if [ "$snappy_mode" = "try" ]; then
    if [ "$snappy_trial_boot" = "1" ]; then
        # Previous boot failed to unset snappy_trial_boot, so toggle
        # rootfs.
        if [ "$snappy_ab" = "a" ]; then
            set snappy_ab=b
        else
            set snappy_ab=a
        fi
        save_env snappy_ab
    else
        # Trial mode so set the snappy_trial_boot (which snappy is
        # expected to unset).
        #
        # Note: don't use the standard recordfail variable since that forces
        # the menu to be displayed and sets an infinite timeout if set.
        set snappy_trial_boot=1
        save_env snappy_trial_boot
    fi
fi

set label="system-$snappy_ab"
set cmdline="root=LABEL=$label ro init=/lib/systemd/systemd console=ttyS0 console=tty1 panic=-1"

menuentry "$label" {
    if [ -e "$prefix/$snappy_ab/vmlinuz" ]; then
        linux $prefix/$snappy_ab/vmlinuz $cmdline
        initrd $prefix/$snappy_ab/initrd.img
    else
        # old-style kernel-in-os-partition
        search --no-floppy --set --label "$label"
        linux /vmlinuz $cmdline
        initrd /initrd.img
    fi
}