While running a bash script, I would like to programmatically re-boot from a USB stick. The bios is set up to boot from the HD. Is this possible? Any hints?
Why do I want to do this??? I'm updating to Ubuntu 20.04 on a hundred or more machines that are installed all over the country in remote locations. I have to export the database and then import it after the updates. The whole process takes hours to run. I want the entire process to happen automatically so the person doing the upgrade doesn't have to babysit.
Thanks for your generous responses. I can give more detail: The bios is set to boot from my hard drive. Grub2 then boots the normal OS.
If I plug in my USB thumb drive, I can boot into Ubuntu from it by hitting the F11 key and selecting the USB thumb drive. So, I'm thinking if I execute sudo update-grub, it should find the OS on the thumb drive and put it in the grub list.
The following are the menuentries in grub.cfg
dfr@m9kmission:~$ grep -i "menuentry '" /boot/grub/grub.cfg
menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-59e8ab4e-1d3d-4a1b-b97b-ec10766929e6' {
menuentry 'Ubuntu, with Linux 4.15.0-112-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.15.0-112-generic-advanced-59e8ab4e-1d3d-4a1b-b97b-ec10766929e6' {
menuentry 'Ubuntu, with Linux 4.15.0-112-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.15.0-112-generic-recovery-59e8ab4e-1d3d-4a1b-b97b-ec10766929e6' {
menuentry 'Ubuntu, with Linux 4.15.0-106-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.15.0-106-generic-advanced-59e8ab4e-1d3d-4a1b-b97b-ec10766929e6' {
menuentry 'Ubuntu, with Linux 4.15.0-106-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.15.0-106-generic-recovery-59e8ab4e-1d3d-4a1b-b97b-ec10766929e6' {
After I run sudo update-grub, the menuentries are the same, the OS on the thumb drive isn't added. Could it be that the os-prober thinks it shouldn't add an entry for a removeable drive? I think if I could get the update-grub to add a menuentry for the os on the thumb drive, I could run sudo grub-reboot and then when I reboot the computer, it would boot from the thumb drive. The next reboot would go back to the normal OS.
Questions:
- Am I thinking correctly?
- How can I get update-grub to make an entry for the os on my thumb drive?
- If I can't, should I insert my own entry into /boot/grub/grub.cfg?
The regular os menuentry is as follows. Maybe I could pattern my new entry after it: (It looks pretty scary though.)
menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-59e8ab4e-1d3d-4a1b-b97b-ec10766929e6' {
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='hd1,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos1 --hint-efi=hd1,msdos1 --hint-baremetal=ahci1,msdos1 59e8ab4e-1d3d-4a1b-b97b-ec10766929e6
else
search --no-floppy --fs-uuid --set=root 59e8ab4e-1d3d-4a1b-b97b-ec10766929e6
fi
linux /boot/vmlinuz-4.15.0-112-generic root=UUID=59e8ab4e-1d3d-4a1b-b97b-ec10766929e6 ro
initrd /boot/initrd.img-4.15.0-112-generic
}
The normal os is on sdb1. The thumb drive is sdc1.
dfr@m9kmission:~$ blkid
/dev/sda1: UUID="d210d958-9eea-4786-9d9f-8311f852b9df" TYPE="ext4" PARTUUID="98f91627-01"
/dev/sdb1: UUID="59e8ab4e-1d3d-4a1b-b97b-ec10766929e6" TYPE="ext4" PARTUUID="4c6a03f4-01"
/dev/sdb2: UUID="32251f52-55d0-4c14-8746-bbf48a3984c0" TYPE="ext4" PARTUUID="4c6a03f4-02"
/dev/sdc1: LABEL="UBUNTU 18_0" UUID="7EF3-2CBA" TYPE="vfat" PARTUUID="0ba7b71d-01"
This is the directory tree on the thumb drive.
dfr@m9kmission:~$ tree -d /media/dfr/UBUNTU\ 18_0/
/media/dfr/UBUNTU 18_0/
├── boot
│ └── grub
│ └── x86_64-efi
├── casper
├── dists
│ └── bionic
│ ├── main
│ │ ├── binary-amd64
│ │ ├── binary-i386
│ │ └── source
│ └── restricted
│ ├── binary-amd64
│ ├── binary-i386
│ └── source
├── EFI
│ └── BOOT
├── install
├── isolinux
├── pics
├── pool
│ ├── main
│ │ ├── b
│ │ │ ├── b43-fwcutter
│ │ │ └── build-essential
│ │ ├── d
│ │ │ ├── dkms
│ │ │ └── dpkg
│ │ ├── f
│ │ │ └── fakeroot
│ │ ├── g
│ │ │ ├── gcc-7
│ │ │ ├── gcc-8
│ │ │ ├── gcc-defaults
│ │ │ ├── glibc
│ │ │ ├── grub2
│ │ │ └── grub2-signed
│ │ ├── l
│ │ │ ├── linux
│ │ │ └── lupin
│ │ ├── liba
│ │ │ ├── libalgorithm-diff-perl
│ │ │ ├── libalgorithm-diff-xs-perl
│ │ │ └── libalgorithm-merge-perl
│ │ ├── m
│ │ │ ├── make-dfsg
│ │ │ ├── manpages
│ │ │ └── mouseemu
│ │ ├── s
│ │ │ ├── setserial
│ │ │ ├── shim
│ │ │ └── shim-signed
│ │ └── u
│ │ ├── ubiquity
│ │ ├── ubiquity-slideshow-ubuntu
│ │ └── user-setup
│ └── restricted
│ └── b
│ └── bcmwl
├── preseed
└── System Volume Information
It looks like the Linux files are in the Casper folder:
dfr@m9kmission:~$ ll /media/dfr/UBUNTU\ 18_0/casper/
total 2121880
drwxr-xr-x 2 dfr dfr 8192 Jul 24 07:14 ./
drwxr-xr-x 13 dfr dfr 8192 Dec 31 1969 ../
-rw-r--r-- 1 dfr dfr 56234 Jul 24 07:14 filesystem.manifest
-rw-r--r-- 1 dfr dfr 767 Jul 24 07:14 filesystem.manifest-minimal-remove
-rw-r--r-- 1 dfr dfr 3309 Jul 24 07:14 filesystem.manifest-remove
-rw-r--r-- 1 dfr dfr 10 Jul 24 07:14 filesystem.size
-rw-r--r-- 1 dfr dfr 2094698496 Jul 24 07:15 filesystem.squashfs
-rw-r--r-- 1 dfr dfr 68622117 Jul 24 07:23 initrd
-rw-r--r-- 1 dfr dfr 9371904 Jul 24 07:24 vmlinuz
Maybe I can edit the new menuentry something like this:
menuentry 'Ubuntu-rescue' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-7EF3-2CBA' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod squashfs
set root='hd3,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd3,msdos1 --hint-efi=hd3,msdos1 --hint-baremetal=ahci1,msdos1 7EF3-2CBA
else
search --no-floppy --fs-uuid --set=root 7EF3-2CBA
fi
linux /casper/vmlinuz root=UUID=7EF3-2CBA ro
initrd /casper/initrd
}
With the above edits, The Ubuntu-rescue is offered in the grub menu. When I boot it, I get a message that says:
error: file `boot/grub/i386-pc/squashfs.mod' not found
I notice on the thumb drive there is a file:
./boot/grub/x86_64-efi/squash4.mod
If I can get grub to look for the file there, it might be getting close.
Any ideas???
Thanks!
