How to restore GRUB on an external HDD?

Question

linux

Guys!
There was a problem with the GRUB bootloader on my main HDD, which has a lot of information. The Linux server was spinning on the computer, and during the next update, I got rough.
When booting from live-cd, there are no results: the installer is rude and returns error 1.
So I put ubuntu server in a new way on another HDD.
What we have: /dev/sda - working clean hdd with new system and working rough and mounted /dev/sdb with non-working rough but important files and system, which is mounted as an external hard drive.
Now, being in a system with /dev/sda, I tried to put GRUB on /dev/sdb according to this instruction: http://help.ubuntu.ru/wiki/restoration_grub
And, unfortunately, nothing happened.
If I write the grub-install /dev/sdb command in the terminal, then it returns an error like this: (sorry for not using screenshots or text here)

If I follow the instructions above and before writing that command, I mount /dev/sdb2 (sdb2 is a section with a Linux server), then it returns the following errors

: Help me please. I don't understand what to do

Answer 1

Your partition is GPT. So you either boot via UEFI, and then the bootloader is placed in the EFI partition.
Either you have legacy, but then you must have a Bios-boot partition. Bite off a 2 megabyte disk partition via gparted and create a bios-boot partition. Then continue installing the hornbeam.