Grub does not see Windows, how to configure?

Question

linux

In total, there are two physical disks - an SSD and a 500GB screw.
Windows is installed on the ssd, Debian Buster is installed on the screw + a 250GB shared partition for Windows and Debian. The most interesting thing is that grud tightly refuses to see Windows, and the Windows bootloader is in order - if you set the bootloader in uefi to boot from the Windows bootloader, which lies on ssd, then Windows will quietly boot, if you set the boot from the screw, grub is loaded, in which there is no Windows. By all means I tried to add the Windows bootloader to the grub menu, in vain. In fstab, all sections are there (sda - screw, sdb - hard drive). os-prober gives empty output.

================================================= ================================
Output from fdisk -l:

[email protected]:~# fdisk -l
Disk /dev/sdb: 111,8 GiB, 120034123776 bytes, 234441648 sectors
Disk model: SPCC Solid State
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: DD22852F-3DBC-4119-B7B2-0AD6D6493D2A

Device       Start       End   Sectors   Size Type
/dev/sdb1     2048   1085439   1083392   529M Windows recovery environment
/dev/sdb2  1085440   1290239    204800   100M EFI System
/dev/sdb3  1290240   1323007     32768    16M Microsoft reserved
/dev/sdb4  1323008 234440703 233117696 111,2G Microsoft basic data


Disk /dev/sda: 465,8 GiB, 500107862016 bytes, 976773168 sectors
Disk model: TOSHIBA DT01ACA0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: D83176BD-F4DA-42E9-AAD8-BD7F15AB0807

Device         Start       End   Sectors   Size Type
/dev/sda1  976510991 976773134    262144   128M Microsoft reserved
/dev/sda2       2048 488282111 488280064 232,9G Linux filesystem
/dev/sda3  488282112 488284159      2048     1M BIOS boot
/dev/sda4  488284160 959838207 471554048 224,9G Linux filesystem
/dev/sda5  959838208 976510975  16672768     8G Linux swap

Partition 1 does not start on physical sector boundary.
Partition table entries are not in disk order.
[email protected]:~#

lsblk:

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 465,8G  0 disk 
├─sda1   8:1    0   128M  0 part 
├─sda2   8:2    0 232,9G  0 part 
├─sda3   8:3    0     1M  0 part 
├─sda4   8:4    0 224,9G  0 part /
└─sda5   8:5    0     8G  0 part [SWAP]
sdb      8:16   0 111,8G  0 disk 
├─sdb1   8:17   0   529M  0 part 
├─sdb2   8:18   0   100M  0 part 
├─sdb3   8:19   0    16M  0 part 
└─sdb4   8:20   0 111,2G  0 part 
[email protected]:~#

blkid:

[email protected]:~# blkid
/dev/sdb1: LABEL="M-PM-^RM-PM->M-QM-^AM-QM-^AM-QM-^BM-PM-0M-PM-=M-PM->M-PM-2M-PM-8M-QM-^BM-QM-^L" UUID="AA7E297E7E294483" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="8b215eea-9cdc-49e4-b5c0-8956325f807a"
/dev/sdb2: UUID="D830-F92B" TYPE="vfat" PARTLABEL="EFI system partition" PARTUUID="fcd2bda0-256b-4eb1-ac53-144c29877db5"
/dev/sdb3: PARTLABEL="Microsoft reserved partition" PARTUUID="e75fb019-c989-4c6f-a330-1cf9731b82db"
/dev/sdb4: UUID="1C92496D92494D08" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="621365b3-1e4c-4dbe-8147-11b5f3271cc2"
/dev/sda1: PARTLABEL="Microsoft reserved partition" PARTUUID="0d7b6c42-6122-11ea-a568-08606e6e194e"
/dev/sda2: PARTUUID="f93c1a83-940c-488f-8147-43d6c4cdf017"
/dev/sda3: PARTUUID="0dbecb52-df73-4f1f-895f-4e93bd857e6f"
/dev/sda4: UUID="fdeac083-9701-4404-aa2b-ecc1ba399250" TYPE="ext4" PARTUUID="555d2e51-22d2-4a53-819c-65376e0e60c5"
/dev/sda5: UUID="053c3b24-c0ca-41e3-aad1-4c4ccb536cd8" TYPE="swap" PARTUUID="aa7bdb7c-f190-4127-8c41-078a85db59af"
[email protected]:~#

etc/grub.d/40_custom:

#!/bin/sh
exec tail -n +3 $0

menuentry "Windows 10" {

  set root=(hd1,2)

  chainloader (hd1,2)+1

}


# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.

PS New to Linux, please explain in simple terms what is wrong with me ..

Answer 1

Попробуйте выполнить в консоли sudo update-grub

Answer 2

У вас не так -- включённый модуль CSM в BIOS/UEFI и не смонтированный в /boot/efi ESP раздел (/dev/sdb2)