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Is there a way to reboot with a different kernel version from the command line? I have Ubuntu PXE booted on a VM, and there is no graphical interface, but I need to downgrade the kernel (which is installed).

marked as duplicate by muru, Eric Carvalho, karel, Community Mar 23 '15 at 17:25

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  • Are you asking how to reboot or how to install a new kernel? – terdon Mar 20 '15 at 16:28

Edit your grub configuration as necessary - if you want to use it for longer, and install the new grub setup then to disk(s).

This I believe will help you understand grub configuration: https://help.ubuntu.com/community/Grub2/Setup

Otherwise I think kexec may also help you.

Install kexec with:

sudo apt-get install kexec-tools
  • 1
    Please edit your answer and explain how the GRUB configuration would be edited and what edits are necessary. As it stands, this is a comment, not an answer. – terdon Mar 20 '15 at 16:28
  • If you want to one-time reboot selection consider using grub-reboot command;
  • If you want to set selection permanently use grub-set-default command.

Bot these commands require MENU-ITEM as parameter, for listing yours see: How to list GRUB's “menuentries” in command-line?

But, you can always hold Shift while booting, to show Grub Menu, isn't it possible in your VM manager?

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