Dual boot Windows 10 / External USB disk with Ubuntu

[urrfaust]

Hello everyone,

I have an issue whiel dual booting Windows 10 and Ubuntu on an external USB disk.
This is the current setup:
- old fujitsu siemens desktop (Esprimo P 5270), about 2008, I think, BIOS is up to date.
- Internal Sata Drive with Windows 10 installed
- External (eSATA) disk used as backup
- External USB Disk with Ubuntu Cosmic
- external USB flash with Ubuntu Live

Windows 10 boots without problems.
The issue is when I try to boot Ubuntu. The GRUB menu does not appear and Windows 10 gets booted. Sometimes, and this I don't really understand, I can access the GRUB menu by pressing F8 just after the BIOS boot sequence. Other times this does not work.
A few more interesting info:

- The Ubuntu external disk boots ok on other pcs
- If I disconnect the internal Win10 disk, Grub menu is displayed and Ubuntu boots OK
- I have tried to install Grub on the second internal SATA disk (the backup one). If I disconnect the Windows 10, Grub menu is displayed. When I reconnect it, I get a grub rescue prompt with "cannot find device..." message

I have attached a screeshot from gparted

And here is the result of parted -l


sudo parted -l
Model: ATA ST3160815AS (scsi)
Disk /dev/sda: 160GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number Start End Size Type File system Flags
1 32.3kB 160GB 160GB primary ntfs boot


Model: ATA ST1000LM048-2E71 (scsi)
Disk /dev/sdb: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags:

Number Start End Size Type File system Flags
1 1049kB 843GB 843GB primary ntfs
2 843GB 1000GB 157GB primary ntfs


Model: Corsair Voyager (scsi)
Disk /dev/sdc: 31.1GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number Start End Size Type File system Flags
1 1049kB 31.1GB 31.1GB primary fat32 boot, lba


Model: WD My Passport 0830 (scsi)
Disk /dev/sdd: 500GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number Start End Size Type File system Flags
1 54.2MB 41.9GB 41.9GB primary ntfs
2 41.9GB 497GB 455GB extended lba
5 41.9GB 42.3GB 365MB logical ext4 boot
6 42.3GB 64.4GB 22.1GB logical ext4
7 64.4GB 497GB 433GB logical ext4
3 497GB 500GB 2746MB primary linux-swap(v1)



and /etc/default/grub



# If yu change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
GRUB_TIMEOUT_STYLE=hidden
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"


bootinfoscript


Boot Info Script 0.61 [1 April 2012]


============================= Boot Info Summary: ===============================

=> Windows is installed in the MBR of /dev/sda.
=> Windows is installed in the MBR of /dev/sdb.
=> Grub2 (v1.99) is installed in the MBR of /dev/sdc and looks at sector 1 of
the same hard drive for core.img. core.img is at this location and looks
in partition 130 for .

sda1: __________________________________________________ ________________________

File system: ntfs
Boot sector type: Windows Vista/7: NTFS
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files: /bootmgr /Boot/BCD /Windows/System32/winload.exe
/ntldr /NTDETECT.COM

sdb1: __________________________________________________ ________________________

File system: ntfs
Boot sector type: Windows Vista/7: NTFS
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files:

sdb2: __________________________________________________ ________________________

File system: ntfs
Boot sector type: Windows Vista/7: NTFS
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files:

sdc1: __________________________________________________ ________________________

File system: ntfs
Boot sector type: Windows XP: NTFS
Boot sector info: No errors found in the Boot Parameter Block.
Operating System: Windows XP
Boot files: /boot.ini /ntldr /NTDETECT.COM

sdc2: __________________________________________________ ________________________

File system: Extended Partition
Boot sector type: -
Boot sector info:

sdc5: __________________________________________________ ________________________

File system: ext4
Boot sector type: Grub2 (v1.99)
Boot sector info: Grub2 (v1.99) is installed in the boot sector of sdc5
and looks at sector 82399874 of the same hard drive
for core.img. core.img is at this location and looks
in partition 130 for .
Operating System:
Boot files: /grub/grub.cfg /extlinux/extlinux.conf

sdc6: __________________________________________________ ________________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System: Ubuntu 18.10
Boot files: /etc/fstab

sdc7: __________________________________________________ ________________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System:
Boot files:

sdc3: __________________________________________________ ________________________

File system: swap
Boot sector type: -
Boot sector info:

============================ Drive/Partition Info: =============================

Drive: sda __________________________________________________ ___________________
Disk /dev/sda: 149,1 GiB, 160041885696 bytes, 312581808 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos

Partition Boot Start Sector End Sector # of Sectors Id System

/dev/sda1 * 63 312,560,639 312,560,577 7 NTFS / exFAT / HPFS


Drive: sdb __________________________________________________ ___________________
Disk /dev/sdb: 931,5 GiB, 1000204886016 bytes, 1953525168 sectors
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: dos

Partition Boot Start Sector End Sector # of Sectors Id System

/dev/sdb1 2,048 1,646,321,663 1,646,319,616 7 NTFS / exFAT / HPFS
/dev/sdb2 1,646,321,664 1,953,519,615 307,197,952 7 NTFS / exFAT / HPFS


Drive: sdc __________________________________________________ ___________________
Disk /dev/sdc: 465,7 GiB, 500074283008 bytes, 976707584 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos

Partition Boot Start Sector End Sector # of Sectors Id System

/dev/sdc1 105,903 81,920,159 81,814,257 7 NTFS / exFAT / HPFS
/dev/sdc2 81,922,048 971,343,871 889,421,824 f W95 Extended (LBA)
/dev/sdc5 * 81,924,096 82,636,799 712,704 83 Linux
/dev/sdc6 82,638,848 125,753,343 43,114,496 83 Linux
/dev/sdc7 125,755,392 971,343,871 845,588,480 83 Linux
/dev/sdc3 971,343,872 976,707,583 5,363,712 82 Linux swap / Solaris


"blkid" output: __________________________________________________ ______________

Device UUID TYPE LABEL

/dev/loop0 squashfs
/dev/loop1 squashfs
/dev/loop10 squashfs
/dev/loop11 squashfs
/dev/loop12 squashfs
/dev/loop13 squashfs
/dev/loop14 squashfs
/dev/loop15 squashfs
/dev/loop2 squashfs
/dev/loop3 squashfs
/dev/loop4 squashfs
/dev/loop5 squashfs
/dev/loop6 squashfs
/dev/loop7 squashfs
/dev/loop8 squashfs
/dev/loop9 squashfs
/dev/sda1 FC20A31C20A2DD40 ntfs
/dev/sdb1 AE74F53474F4FFBF ntfs External
/dev/sdb2 EE6608AD6608791B ntfs Backup
/dev/sdc1 187C5C427C5C1D36 ntfs Windows
/dev/sdc3 5e20e480-272f-455a-802d-ea42bb902656 swap
/dev/sdc5 f316c437-0b83-4111-8c61-79134d213b0f ext4 boot
/dev/sdc6 811ae150-da31-4652-93bb-8ce73dc3c93e ext4
/dev/sdc7 d999457a-97db-4724-8a71-e6d08ba55709 ext4 home

================================ Mount points: =================================

Device Mount_Point Type Options

/dev/sdb1 /media/simone/External fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,def ault_permissions,allow_other,blksize=4096,uhelper= udisks2)
/dev/sdb2 /media/simone/Backup fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,def ault_permissions,allow_other,blksize=4096,uhelper= udisks2)
/dev/sdc1 /media/simone/Windows fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,def ault_permissions,allow_other,blksize=4096,uhelper= udisks2)
/dev/sdc5 /boot ext4 (rw,relatime)
/dev/sdc6 / ext4 (rw,relatime,errors=remount-ro)
/dev/sdc7 /home ext4 (rw,relatime,stripe=32738)


================================ sdc1/boot.ini: ================================

--------------------------------------------------------------------------------
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOW S
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /bootlog
[spybotsd]
timeout.old=30
--------------------------------------------------------------------------------

============================= sdc5/grub/grub.cfg: ==============================

--------------------------------------------------------------------------------
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
set have_grubenv=true
load_env
fi
if [ "${initrdfail}" = 2 ]; then
set initrdfail=
elif [ "${initrdfail}" = 1 ]; then
set next_entry="${prev_entry}"
set prev_entry=
save_env prev_entry
if [ "${next_entry}" ]; then
set initrdfail=2
fi
fi
if [ "${next_entry}" ] ; then
set default="${next_entry}"
set next_entry=
save_env next_entry
set boot_once=true
else
set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
menuentry_id_option="--id"
else
menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
set saved_entry="${prev_saved_entry}"
save_env saved_entry
set prev_saved_entry=
save_env prev_saved_entry
set boot_once=true
fi

function savedefault {
if [ -z "${boot_once}" ]; then
saved_entry="${chosen}"
save_env saved_entry
fi
}
function initrdfail {
if [ -n "${have_grubenv}" ]; then if [ -n "${partuuid}" ]; then
if [ -z "${initrdfail}" ]; then
set initrdfail=1
if [ -n "${boot_once}" ]; then
set prev_entry="${default}"
save_env prev_entry
fi
fi
save_env initrdfail
fi; fi
}
function recordfail {
set recordfail=1
if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi
}
function load_video {
if [ x$feature_all_video_module = xy ]; then
insmod all_video
else
insmod efi_gop
insmod efi_uga
insmod ieee1275_fb
insmod vbe
insmod vga
insmod video_bochs
insmod video_cirrus
fi
}

if [ x$feature_default_font_path = xy ] ; then
font=unicode
else
insmod part_msdos
insmod ext2
set root='hd2,msdos6'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos6 --hint-efi=hd2,msdos6 --hint-baremetal=ahci2,msdos6 811ae150-da31-4652-93bb-8ce73dc3c93e
else
search --no-floppy --fs-uuid --set=root 811ae150-da31-4652-93bb-8ce73dc3c93e
fi
font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
set gfxmode=auto
load_video
insmod gfxterm
set locale_dir=$prefix/locale
set lang=C
insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ] ; then
set timeout=30
else
if [ x$feature_timeout_style = xy ] ; then
set timeout_style=hidden
set timeout=10
# Fallback hidden-timeout code in case the timeout_style feature is
# unavailable.
elif sleep --interruptible 10 ; then
set timeout=0
fi
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
if background_color 44,0,30,0; then
clear
fi
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
function gfxmode {
set gfxpayload="${1}"
if [ "${1}" = "keep" ]; then
set vt_handoff=vt.handoff=1
else
set vt_handoff=
fi
}
if [ "${recordfail}" != 1 ]; then
if [ -e ${prefix}/gfxblacklist.txt ]; then
if hwmatch ${prefix}/gfxblacklist.txt 3; then
if [ ${match} = 0 ]; then
set linux_gfx_mode=keep
else
set linux_gfx_mode=text
fi
else
set linux_gfx_mode=text
fi
else
set linux_gfx_mode=keep
fi
else
set linux_gfx_mode=text
fi
export linux_gfx_mode
menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-811ae150-da31-4652-93bb-8ce73dc3c93e' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
linux /vmlinuz-4.18.0-20-generic root=UUID=811ae150-da31-4652-93bb-8ce73dc3c93e ro quiet splash $vt_handoff
initrd /initrd.img-4.18.0-20-generic
}
submenu 'Advanced options for Ubuntu' $menuentry_id_option 'gnulinux-advanced-811ae150-da31-4652-93bb-8ce73dc3c93e' {
menuentry 'Ubuntu, with Linux 4.18.0-20-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.18.0-20-generic-advanced-811ae150-da31-4652-93bb-8ce73dc3c93e' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
echo 'Loading Linux 4.18.0-20-generic ...'
linux /vmlinuz-4.18.0-20-generic root=UUID=811ae150-da31-4652-93bb-8ce73dc3c93e ro quiet splash $vt_handoff
echo 'Loading initial ramdisk ...'
initrd /initrd.img-4.18.0-20-generic
}
menuentry 'Ubuntu, with Linux 4.18.0-20-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.18.0-20-generic-recovery-811ae150-da31-4652-93bb-8ce73dc3c93e' {
recordfail
load_video
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
echo 'Loading Linux 4.18.0-20-generic ...'
linux /vmlinuz-4.18.0-20-generic root=UUID=811ae150-da31-4652-93bb-8ce73dc3c93e ro recovery nomodeset
echo 'Loading initial ramdisk ...'
initrd /initrd.img-4.18.0-20-generic
}
menuentry 'Ubuntu, with Linux 4.18.0-10-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.18.0-10-generic-advanced-811ae150-da31-4652-93bb-8ce73dc3c93e' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
echo 'Loading Linux 4.18.0-10-generic ...'
linux /vmlinuz-4.18.0-10-generic root=UUID=811ae150-da31-4652-93bb-8ce73dc3c93e ro quiet splash $vt_handoff
echo 'Loading initial ramdisk ...'
initrd /initrd.img-4.18.0-10-generic
}
menuentry 'Ubuntu, with Linux 4.18.0-10-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.18.0-10-generic-recovery-811ae150-da31-4652-93bb-8ce73dc3c93e' {
recordfail
load_video
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
echo 'Loading Linux 4.18.0-10-generic ...'
linux /vmlinuz-4.18.0-10-generic root=UUID=811ae150-da31-4652-93bb-8ce73dc3c93e ro recovery nomodeset
echo 'Loading initial ramdisk ...'
initrd /initrd.img-4.18.0-10-generic
}
}

### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###

### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry 'Memory test (memtest86+)' {
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
knetbsd /memtest86+.elf
}
menuentry 'Memory test (memtest86+, serial console 115200)' {
insmod part_msdos
insmod ext2
set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f
else
search --no-floppy --fs-uuid --set=root f316c437-0b83-4111-8c61-79134d213b0f
fi
linux16 /memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
menuentry 'Windows 10 (on /dev/sda1)' --class windows --class os $menuentry_id_option 'osprober-chain-FC20A31C20A2DD40' {
insmod part_msdos
insmod ntfs
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 FC20A31C20A2DD40
else
search --no-floppy --fs-uuid --set=root FC20A31C20A2DD40
fi
parttool ${root} hidden-
drivemap -s (hd0) ${root}
chainloader +1
}
menuentry 'Microsoft Windows XP Professional (on /dev/sdc1)' --class windows --class os $menuentry_id_option 'osprober-chain-187C5C427C5C1D36' {
insmod part_msdos
insmod ntfs
set root='hd2,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos1 --hint-efi=hd2,msdos1 --hint-baremetal=ahci2,msdos1 187C5C427C5C1D36
else
search --no-floppy --fs-uuid --set=root 187C5C427C5C1D36
fi
parttool ${root} hidden-
drivemap -s (hd0) ${root}
chainloader +1
}
set timeout_style=menu
if [ "${timeout}" = 0 ]; then
set timeout=10
fi
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/30_uefi-firmware ###
### END /etc/grub.d/30_uefi-firmware ###

### BEGIN /etc/grub.d/40_custom ###
# 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.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f ${config_directory}/custom.cfg ]; then
source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f $prefix/custom.cfg ]; then
source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###
--------------------------------------------------------------------------------

========================= sdc5/extlinux/extlinux.conf: =========================

--------------------------------------------------------------------------------
## /boot/extlinux/extlinux.conf
##
## IMPORTANT WARNING
##
## The configuration of this file is generated automatically.
## Do not edit this file manually, use: extlinux-update


default l0
prompt 1
timeout 50

include themes/debian/theme.cfg
--------------------------------------------------------------------------------

=================== sdc5: Location of files loaded by Grub: ====================

GiB - GB File Fragment(s)


================= sdc5: Location of files loaded by Syslinux: ==================

GiB - GB File Fragment(s)


============== sdc5: Version of COM32(R) files used by Syslinux: ===============

extlinux/chain.c32 : COM32R module (v4.xx)

=============================== sdc6/etc/fstab: ================================

--------------------------------------------------------------------------------
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sdd6 during installation
UUID=811ae150-da31-4652-93bb-8ce73dc3c93e / ext4 errors=remount-ro 0 1
# /boot was on /dev/sdd5 during installation
UUID=f316c437-0b83-4111-8c61-79134d213b0f /boot ext4 defaults 0 2
# /home was on /dev/sdd7 during installation
UUID=d999457a-97db-4724-8a71-e6d08ba55709 /home ext4 defaults 0 2
# swap was on /dev/sdd3 during installation
UUID=5e20e480-272f-455a-802d-ea42bb902656 none swap sw 0 0
--------------------------------------------------------------------------------

=================== sdc6: Location of files loaded by Grub: ====================

GiB - GB File Fragment(s)


============== sdc6: Version of COM32(R) files used by Syslinux: ===============

boot/extlinux/chain.c32 : COM32R module (v4.xx)

=============================== StdErr Messages: ===============================

cat: /tmp/BootInfo-fI03kqG8/Tmp_Log: File o directory non esistente
cat: /tmp/BootInfo-fI03kqG8/Tmp_Log: File o directory non esistente
cat: /tmp/BootInfo-fI03kqG8/Tmp_Log: File o directory non esistente

[yancek]

Your output shows 4 hard drives of varying sizes. 3 have only windows partitions while the 3rd (sdd 500GB drive) has both windows and Linux partitions. The bootinfoscript output shows that you installed Grub boot code to the MBR of sdc (31GB drive) and your Ubuntu is on sdd. If you can boot Ubuntu, you should install Grub to the MBR of sdd: sudo grub-install /dev/sdd and after doing that run: sudo update-grub and then set the 500GB drive (sdd) to first boot priority in the BIOS.

Is your windows 10 and update from 7? It's a bit unusual to have windows 10 on a Legacy drive and not UEFI/GPT.

I'm not sure if the bootinfoscript output is correct as you say you can boot Ubuntu on the external drive but bootinfoscript shows no boot code in the MBR? You might try setting sdd to first boot priority in the BIOS or sdc which shows boot code in the MBR?

[oldfred]

Not sure how you are booting. Grub in MBR does not look correct, is it using a Windows boot loader to load the grub in the partition boot sector. That is not a particularly good way.

I would reinstall grub to MBR of sdc.
But with you multiple external drives you may have drive number issues. I have that when I boot an install from my flash drive.
You show this which BIOS, grub see as third drive, hd0, hd1 & hd2. But if you directly boot the hd2 drive, it is the hd0. And if you plug drives in a different order it may be anything. I often have boot error, realize my drive order has changed and in grub manually edit the hd2 to hd0. In some cases I was not sure what drive it was and experimented until it worked.
set root='hd2,msdos5'

It is supposed to use UUID, and find that, but sometimes with external drives it stops looking and gets lost?

[urrfaust]

Yes I did an upgrade Win7->Win10.
I did install grub to sdd but to no avail.


Your output shows 4 hard drives of varying sizes. 3 have only windows partitions while the 3rd (sdd 500GB drive) has both windows and Linux partitions. The bootinfoscript output shows that you installed Grub boot code to the MBR of sdc (31GB drive) and your Ubuntu is on sdd. If you can boot Ubuntu, you should install Grub to the MBR of sdd: sudo grub-install /dev/sdd and after doing that run: sudo update-grub and then set the 500GB drive (sdd) to first boot priority in the BIOS.

Is your windows 10 and update from 7? It's a bit unusual to have windows 10 on a Legacy drive and not UEFI/GPT.

I'm not sure if the bootinfoscript output is correct as you say you can boot Ubuntu on the external drive but bootinfoscript shows no boot code in the MBR? You might try setting sdd to first boot priority in the BIOS or sdc which shows boot code in the MBR?

[urrfaust]

How do you see that a Windows boot loader is loading grub in the partition boot sector?
How do I check what grub sees what?


Not sure how you are booting. Grub in MBR does not look correct, is it using a Windows boot loader to load the grub in the partition boot sector. That is not a particularly good way.

I would reinstall grub to MBR of sdc.
But with you multiple external drives you may have drive number issues. I have that when I boot an install from my flash drive.
You show this which BIOS, grub see as third drive, hd0, hd1 & hd2. But if you directly boot the hd2 drive, it is the hd0. And if you plug drives in a different order it may be anything. I often have boot error, realize my drive order has changed and in grub manually edit the hd2 to hd0. In some cases I was not sure what drive it was and experimented until it worked.
set root='hd2,msdos5'

It is supposed to use UUID, and find that, but sometimes with external drives it stops looking and gets lost?

[oldfred]

Did drive change to sdd? Then it will install as hd3, but when directly booting it needs to be hd0.
When booting if you get grub menu, change boot entry to hd0.

Re-looking at it the grub in the partition boot sector also refers to partition 130. Not sure if its grub or old version of bootinfoscript. Try using Boot-Repair from Ubuntu live installer.

=> Grub2 (v1.99) is installed in the MBR of /dev/sdc and looks at sector 1 of
the same hard drive for core.img. core.img is at this location and looks
in partition 130 for .

sdc5: _______________________________________

File system: ext4
Boot sector type: Grub2 (v1.99)
Boot sector info: Grub2 (v1.99) is installed in the boot sector of sdc5
and looks at sector 82399874 of the same hard drive
for core.img. core.img is at this location and looks
in partition 130 for .


Only install grub to MBR of drive with Ubuntu. Some USB boot configurations have the now very old BIOS issue of boot files must be near (within first 137GB) of a drive. New UEFI based systems do not have this issue. You have a /boot and smaller / (root) inside the normal limit, but do have a larger NTFS partition at beginning of drive. Should not be an issue.

May be best to see details, use ppa version with your live installer (2nd option) or any working install, not older Boot-Repair ISO:
Please copy & paste link to the Boot-info summary report ( do not post report), the auto fix sometimes can create more issues.
https://help.ubuntu.com/community/Boot-Repair &
https://sourceforge.net/p/boot-repair/home/Home/

[urrfaust]

boot-info report http://paste.ubuntu.com/p/qX2yVgVsrd/

[oldfred]

It still looks like a drive order issue.
All your drives want to be first, or need to be first when booted.

Only if Boot-Repair does not overwrite the Windows boot loader in sda, should you run the autofix. With internal drives, it always wants to install grub to every MBR, but with external drives it knows to only install it to the external drive's MBR.

But when booting you may have to edit the grub entries to be the correct hdX. When directly booted it it hd0, When booted from another drive it may be hd1. But external drives mount depending on BIOS, so you may just have to experiment.

At grub menu, use e for edit and change hdX to correct drive. Depending on which grub you are using, it may vary.


set root='hd2,msdos5'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos5 --hint-efi=hd2,msdos5 --hint-baremetal=ahci2,msdos5 f316c437-0b83-4111-8c61-79134d213b0f

If booting directly from external, all the 2 should be 0. But if from grub on internal drive, it may be 1 or some other drive number.
If once you boot from external's grub, run this and it will update those entries to all be 0.
sudo update-grub

[urrfaust]

I tried changing hd2 to hd0 in grub and ran update-grub. Restarted and it still booted win10.
It seems that grub menu shows up only when I turn on the pc i.e. cold start. If I restart it, it doesn’t show. It is probably a BIOS issue

[urrfaust]

Also, looking at /boot/grub/grub.cfg I see that it’s using hd2 all over the place. Could it be that the grub boot loader installed in the mbr of the second disk sdb is messing up the whole thing. How do I get rid of it? sdb is just an NTFS formatted disk I use for backup (pics, movies etc)

[yancek]

You have a grub.cfg file on sdc5 with the Ubuntu menuentries and another grub.cfg on sdc6 with only windows entries?? Unusual to say the least.

Have you set sdc, the 465GB drive to first boot priority in the BIOS of your computer?? Grub is in the MBR of this drive and the boot files are also on this drive (partition sdc5) with Ubuntu entries so setting this to first boot priority should boot Ubuntu. Not sure how/why you have Grub files on 2 partitions?


I tried changing hd2 to hd0 in grub and ran update-grub

How? If you edited the grub.cfg file directly the change will not be saved if you update grub. You need to change the entry in a file in /etc/grub.d/ and then run update grub.
I'm not sure why you are concerned with sdb. You need to set the correct drive (sdc) first in boot priority.

[urrfaust]

Yes I have set sdc to be the first in the boot order in BIOS.
I changed hd2 to hd0 in the grub menu at boot, by pressing 'e'. Then I ran update-grub. But then in grub.cfg I see hd2.
I'm wondering if the disk numbering hd0, hd1... changes between reboots???

[oldfred]

If plug in a drive, flash drive or unplug it, or reboot, drive order can change.

I thought if you directly boot from sdc, that would be seen as hd0 in grub.
My old system that was BIOS, boot drive always was hd0 and I booted from just about every drive, but they were all internal. Only my flash drives were external and I normally only had one plugged in at a time and it always was sdf when plugged in and sda when rebooted if still plugged in.

But BIOS does keep track of drive order primarily by SATA port order. Its just flash drives or other external drives may change that.

[yancek]

changed hd2 to hd0 in the grub menu at boot, by pressing 'e'. Then I ran update-grub. But then in grub.cfg I see hd2.

Changing a menuentry by using the e key to edit it on boot is one time only. Nothing is saved. Not sure why you ran update-grub. If you change the hd2 to hd0 for test purposes in the grub.cfg menu, do NOT run update-grub as the change will be overwritten when you update grub. If you are just testing, doing it with the e key on boot is simpler. What happened when you changed the entry on boot with the e key to hd0? If it boots correctly, you would then need to edit the 40_custom or another file in /etc/grub.d directory to make the change permanent.

[urrfaust]

Yes it booted when I changed it to hd0. Anyway i’m Thinking this is a timing issue with the usb disk. Whenever the pc is rebooted, I don’t get the grub menu. If I turn it on, or, if I disconnect/reconnect it between boots, then It works. probably at reboot, the USB port does not get reset or something

[yancek]

I'm not sure what the problem is but, if it booted when you changed the entry to hd0, try booting again and then copy the menuentry for Ubuntu to the file: /etc/grub.d/40_custom. Make sure you change the entry so that it shows hd0 rather than hd2, save the file (need to use sudo for root privileges to edit this file) then run sudo update-grub. If that doesn't work, I'm not sure what else you could do.