[CentOS] 8.2.2004 Latest yum update renders machine unbootable

Fri Jul 31 16:24:51 UTC 2020
Alessandro Baggi <alessandro.baggi at gmail.com>

Il 31/07/20 13:08, ja ha scritto:
> On Fri, 2020-07-31 at 22:35 +1200, Alan McRae via CentOS wrote:
>> I am running an Intel x64 machine using UEFI to boot an SSD.
>>
>> Installing the latest yum update which includes grub2 and kernel
>> 4.18.0-193.14.2.el8_2.x86_64 renders the machine unbootable, blank
>> screen where grub should be, no error messages, just hangs.
>>
>> After some hours I managed to modify another bootable partition
>> (containing older software) and boot it from there.
>>
>> After that, I  found out it is a known problem.
>>
>> The main point of this message is to make people aware of the problem
>> and suggest admins don't run 'yum update' until they understand the
>> problem and have a fix at hand.
>>
>> See 'UEFI boot blank screen post update' for a solution and directions
>> to the redhat article.
>>
>> Regards
>>
>> Alan
>>
> I have been punished by this bug - it is/was very nasty.
>
Me too. Luckily it happened on a test machine.

Sorry but seems that those packages were not tested before pushing them 
in the update repo. Would be great to know what happened to the 
mainstream chains and how a package like grub reached the update repo 
when it has serious problem (genuine curiosity but not to blame them).

In my case, the restore procedure reported by RH in case of reboot does 
not work and reports that the packages are already at the lowest version 
and that the downgrade is not possibile. I don't know why.