[CentOS] Centos 7 shim fix failed

Tue Aug 4 23:27:15 UTC 2020
david <david at daku.org>

At 04:18 PM 8/4/2020, you wrote:
>Am 05.08.20 um 01:09 schrieb david:
>>At 01:54 PM 8/4/2020, you wrote:
>>>On Tue, 04 Aug 2020 13:44:05 -0700
>>>david wrote:
>>> > After all the updates, the system was NOT bootable.
>>>How long did you wait for it to boot, and what 
>>>did it do when it failed to boot?  What text 
>>>messages showed up on the console?  Any 
>>>reported errors when you ran the update or 
>>>when you rebooted the computer?  If so, what did the say?
>>>I personally haven't had any issues updating 
>>>any of my computers (using a mix of Centos 6, 
>>>7 and 8) but maybe they're all too old to for the issue to show up.
>>How long did I wait:Â  5 minutes
>>What on the console:Â  nothing, just a dull gray color
>>Errors on update:Â  none
>>But when I blocked the update, it booted within a minute, and ran.
>Can you boot the system with all updates and secureboot=off?
>(Just to be sure; I imply that you use UEFI, right?)

I'm not sure how to turn 'secure boot' off or if 
it exists.  (MacMini5.2).  I presume it uses 
UEFI, but not sure how to answer that.

Boot failure only occurs when the grub2/shim/mokutil updates are applied.