Why does one can't boot from base kernel version during kernel downgrade & Menuentry text in the grub2.cfg for base kernel version changes after executing grub2-mkconfig?
Issue
- In Red Hat Enterprise Linux 7.1 environment, in order to downgrade the kernel version fromlets say
3.10.0-327.10.1.el7.x86_64
to the base kernel version3.10.0-229.el7.x86_64
,grub2. cfg
has to be edited so as to point to themenuentry
of the base kernel version. -
To perform the downgrade, following steps are executed:
- In the updated state, retrieve the
menuentry
of the base kernel version from thegrub2.cfg
file. Referred the Documentation - The
menuentry
for the base kernel version obtained from step 1 ismenuentry
Red Hat Enterprise Linux Server 7.1 (Maipo), with Linux 3.10.0-229.el7.x86_64 - Set the above menu entry in the
/boot/grub/grubenv
(GRUB_DEFAULT is pointing to saved) by issuing thegrub2-set-default
command. - Execute the
grub2-mkconfig
command.
- In the updated state, retrieve the
-
Observation:
- After executing
grub2-mkconfig
, it is observed that menu title for the base kernel version ingrub2.cfg
changes frommenuentry
Red Hat Enterprise Linux Server 7.1 (Maipo), with Linux 3.10.0-229.el7.x86_64 tomenuentry
Red Hat Enterprise Linux Server (3.10.0-229.el7.x86_64) 7.1 (Maipo) - Now, when the system is rebooted, the
saved_entry
has a textmenuentry
Red Hat Enterprise Linux Server 7.1 (Maipo), with Linux 3.10.0-229.el7.x86_64, which is not present in thegrub2.cfg
. Hence when the system boots up, it is unable to find thesaved_entry
and doesn't boot from the base kernel version as a result of the inconsistency in the text in thegrub2.cfg
and thesaved_entry
in thegrubenv
file.
- After executing
-
Is this a bug? What can be the solution?
Environment
- Red Hat Enterprise Linux 7.1
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