I have 2 disks (/dev/sda and /dev/sdb) on UEFI laptop. Both GPT.
sda1 - NTFS - Windows, sda2 - FAT32 - EFI partition where is Windows Boot Manager and GRUB sdb1 - NTFS - another windows sdb2 - NTFS - My data sdb3 - FAT32 - EFI partition sdb4 - EXT4 - Debian
in EFI order i can see Windows Boot Manager and GRUB. I can change between then and thats working. I consider to use syslinux to boot to debian. I want to have syslinux on sdb3, I mounted that and copy these files to this partition at the location:
/EFI/SYSLINUX/initrd.img /EFI/SYSLINUX/ldlinux.e64 /EFI/SYSLINUX/syslinux.cfg /EFI/SYSLINUX/syslinux.efi /EFI/SYSLINUX/vmlinuz
vmlinuz and initrd i copied from sdb4\boot and rename. syslinux.efi and ldlinux.e64 i copied from syslinux-6.03.tar.gz downloaded from http://kernel.org. syslinux.cfg i wrote and contents is
PROMPT 0 TIMEOUT 300 DEFAULT deb LABEL deb LINUX vmlinuz APPEND ROOT=/dev/sdb4 INITRD initrd.img
then i added record to EFI via command
efibootmgr -c -d /dev/sdb3 -p 1 -l \\EFI\\SYSLINUX\\syslinux.efi -L "SYSLINUX2"
efiboot manager responded success and shows SYSLINUX2 as boot options but when i reboot computer (by reboot command) and goes to UEFI settings, there is no SYSLINUX2 option added. There are only GRUB and Windows Boot Manager. After next boot to debian, efibootmgr too responses only Windows Boot Manager and GRUB.
I have read that some people had problems with secure boot. I have disabled it and GRUB have not problem with this.
What is wrong? How to make efibootmgr setting persistent? Where i did mistake (if any)?