CentOS 7 Update will not boot latest kernel

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Grantnoturbus
Posts: 11
Joined: 2021/05/26 15:52:19

CentOS 7 Update will not boot latest kernel

Post by Grantnoturbus » 2021/05/26 16:13:55

Hello Wise and Noble Linux Gurus,

Just ran latest CentOS 7 updates using the Application Installer and could not boot into the latest kernel.
Just got 2 lines of various red characters on the top of the screen.
I was able to boot into the pervious kernel, thank the maker, as this is our production mail server.

Not sure if I can just keep running off the previous kernel? I would like to update.
When I checked for updates in Application Installer again on the previous kernel, it shows no updates available.

Fairly new to Linux. Have never had issues updating and not sure what the issue is, please help!

This is a CentOS 7 VM running on Hyper-V 2016.

Code: Select all

[root@ axadmin]# df -lhT
Filesystem              Type      Size  Used Avail Use% Mounted on
devtmpfs                devtmpfs  1.9G     0  1.9G   0% /dev
tmpfs                   tmpfs     1.9G   38M  1.9G   2% /dev/shm
tmpfs                   tmpfs     1.9G   18M  1.9G   1% /run
tmpfs                   tmpfs     1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/centos-root xfs        50G  9.8G   41G  20% /
/dev/sda1               xfs      1014M  382M  633M  38% /boot
/dev/sdb1               ext4      237G   57G  168G  26% /opt/zimbra
/dev/mapper/centos-home xfs       186G   81G  105G  44% /home
tmpfs                   tmpfs     377M     0  377M   0% /run/user/989
tmpfs                   tmpfs     377M   40K  377M   1% /run/user/1000
[root@ axadmin]# rpm -qa kernel\* \*release | sort
centos-release-7-9.2009.1.el7.centos.x86_64
kernel-3.10.0-1127.19.1.el7.x86_64
kernel-3.10.0-1160.11.1.el7.x86_64
kernel-3.10.0-1160.15.2.el7.x86_64
kernel-3.10.0-1160.2.2.el7.x86_64
kernel-3.10.0-1160.25.1.el7.x86_64
kernel-headers-3.10.0-1160.25.1.el7.x86_64
kernel-tools-3.10.0-1160.25.1.el7.x86_64
kernel-tools-libs-3.10.0-1160.25.1.el7.x86_64
[root@ axadmin]# yum list installed kernel
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: centos.les.net
 * extras: muug.ca
 * updates: centos.les.net
Installed Packages
kernel.x86_64                   3.10.0-1127.19.1.el7                    @updates
kernel.x86_64                   3.10.0-1160.2.2.el7                     @updates
kernel.x86_64                   3.10.0-1160.11.1.el7                    @updates
kernel.x86_64                   3.10.0-1160.15.2.el7                    @updates  ( currently booted to this )
kernel.x86_64                   3.10.0-1160.25.1.el7                    @updates
Last edited by Grantnoturbus on 2021/06/01 17:25:50, edited 1 time in total.

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TrevorH
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Location: Brighton, UK

Re: CentOS 7 Update will not boot latest kernel

Post by TrevorH » 2021/05/26 16:28:01

Start by trying yum reinstall kernel-3.10.0-1160.25.1.el7.x86_64 and see i f that helps. Sometimes, if yum is interrupted mid-run, it will leave a kernel half installed and unbootable. The reinstall will sort that out if that's what the problem is and confirm that it's a real problem if it doesn't.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

Grantnoturbus
Posts: 11
Joined: 2021/05/26 15:52:19

Re: CentOS 7 Update will not boot latest kernel

Post by Grantnoturbus » 2021/05/26 16:35:11

Thank you for the reply.
I will have to try this command tomorrow morning, as I cannot reboot or interrupt this server during working hours.

From what I have read, there should be no issues running off the previous kernel, other than if I reboot and it tries to load the latest again?
Everything seems to be functional on the previous kernel.
As in I can wait a bit to try to fix this?

Grantnoturbus
Posts: 11
Joined: 2021/05/26 15:52:19

Re: CentOS 7 Update will not boot latest kernel

Post by Grantnoturbus » 2021/05/27 13:18:16

yum reinstall the latest kernel was successful, no error.

Still cannot boot to this new kernel.

All I get when I boot to it is a flashing black cursor for 1 or 2 seconds, then it goes immediately to two lines of red characters spaced out across the screen. The characters are not text, just two red characters separated by a tab then over and over for two lines, characters are different. No text ever appears. It just hangs at this screen.

The other weird thing is my caps lock and scroll lock on my keyboard start flashing. I am remote connected with the Hyper-V manager console.

Guess it looks like I am staying on the previous kernel for a bit, as I have no idea what the issue is.

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TrevorH
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Re: CentOS 7 Update will not boot latest kernel

Post by TrevorH » 2021/05/27 13:28:47

The other weird thing is my caps lock and scroll lock on my keyboard start flashing
That means it did a kernel panic.

Try it again but this time make sure you remove 'rhgb' and 'quiet' from the kernel command line before you boot - that can be done from the grub menu at boot time by hitting 'e' to edit the entry, amending the linux16/linuxefi line to remove those and then hitting ctrl-x to continue. It will still panic but this time you will see the panic output and can take a picture and post it.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

Grantnoturbus
Posts: 11
Joined: 2021/05/26 15:52:19

Re: CentOS 7 Update will not boot latest kernel

Post by Grantnoturbus » 2021/05/27 13:48:38

Thank you for continuing to assist me with this.

Will try this tomorrow morning and post the additional information.

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TrevorH
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Location: Brighton, UK

Re: CentOS 7 Update will not boot latest kernel

Post by TrevorH » 2021/05/27 14:20:00

Do you have any Microsoft hyper-v packages installed?
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

Grantnoturbus
Posts: 11
Joined: 2021/05/26 15:52:19

Re: CentOS 7 Update will not boot latest kernel

Post by Grantnoturbus » 2021/05/27 14:23:20

This is a CentOS VM running on a Hyper-V 2016 host. I am accessing it with Hyper-V manager running on Windows 10 connected to the host. The previous kernel and others before have worked great.

Not exactly sure what you mean by hyper-V packages installed? In the CentOS? I don't think I installed anything hyper-v related in the CentOS.

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TrevorH
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Re: CentOS 7 Update will not boot latest kernel

Post by TrevorH » 2021/05/27 14:54:56

I believe that MS have their own packages that are to be installed in guests to improve the "experience". Similar to VMWare's Guest Tools and VBox's VBox Additions. I was wondering if you had any of those installed or were relying on the in-kernel versions of those modules to support e.g. virtual network/video adapters etc.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

Grantnoturbus
Posts: 11
Joined: 2021/05/26 15:52:19

Re: CentOS 7 Update will not boot latest kernel

Post by Grantnoturbus » 2021/05/27 15:09:44

Fairly certain I did not install any of these as it was working for what I needed without them. Not sure what to look for or how.

I may have ran this:
$sudo grubby --update-kernel=ALL --args="video=hyperv_fb:1600x1028"
$sudo reboot

Installed nano, Bind, and Zimbra as this is our email server, other than that I do not think I installed anything else.

It is BIOS not UEFI, generation 1, two IDE drives, has OS shutdown, TIme Sync, Data Exchange, Heartbeat and Backup(VSS) integration services on.

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