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grub2-ubuntu-add-kernel-parameters-that-survive-updates
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grub2-ubuntu-add-kernel-parameters-that-survive-updates
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.. _grub2-ubuntu-add-kernel-parameters-that-survive-updates-1:

Grub2 ubuntu add kernel parameters that survive updates
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If your Ubuntu Kernel is updated your kernel parameters will be lost. In
my case one of my IBM systems will not boot unless *iommu=soft* exists
as a kernel boot parameter. To make this change survive after kernel
updates do the following.

edit **/etc/default/grub** and add the entry to
**GRUB_CMDLINE_LINUX_DEFAULT**:

.. code-block:: grub

GRUB_CMDLINE_LINUX_DEFAULT=“quiet splash iommu=soft”

You can also make changes to grub 2 during system start-up by pressing
‘e’ and then ‘f10’ to boot. I had to change hd(1,msdos1) to hd(1,5). To
make this change permanent when the OS booted I ran:

.. code-block:: grub

update-grub