doteď jsem měl jen mbr (ověřeno přes gdisk)

a ty chyby:

~ % sudo grub-install  /dev/sdb --boot-directory /run/media/dd/φ/Boot/grub/          
/usr/bin/grub-bios-setup: warning: Attempting to install GRUB to a disk with multiple partition labels.  This is not supported yet..
/usr/bin/grub-bios-setup: warning: Embedding is not possible.  GRUB can only be installed in this setup by using blocklists.  However, blocklists are UNRELIABLE and their use is discouraged..
/usr/bin/grub-bios-setup: error: will not proceed with blocklists.
1 

~ % sudo grub-install  /dev/sdb1 --boot-directory /run/media/dd/φ/Boot/grub/
/usr/bin/grub-bios-setup: warning: File system `ntfs' doesn't support embedding.
/usr/bin/grub-bios-setup: warning: Embedding is not possible.  GRUB can only be installed in this setup by using blocklists.  However, blocklists are UNRELIABLE and their use is discouraged..
/usr/bin/grub-bios-setup: error: will not proceed with blocklists.
1