Always Boot From Elrepo Kernel

Home » CentOS » Always Boot From Elrepo Kernel
CentOS 5 Comments

Hello All,

I purchased some Dell Latitude 3570 laptops. They came with Ubuntu preinstalled. ( Which I swapped for CentOS7)
I have to use Elrepo kernel on these machines to get some of the fn function keys to work. So I installed Elrepo’s kernel-ml and selected this kernel with:
# grub2-set-default 0
( after disabling secure boot)

The problem I see is that after a next kernel update, the new CentOS kernel will be nr 0 and the machine will boot from that kernel if I tested this correctly.

Is there a way I can enable elrepo kernel update but not the regular CentOS kernel?

Many thanks, J.

5 thoughts on - Always Boot From Elrepo Kernel

  • I believe you need to update /etc/sysconfig/kernel to set the ‘default’
    kernel package to be the kernel-ml or whichever elrepo kernel you’re using.

  • –MqF2aGr7UI7UwlDvL6nQShnLUTJ8nhurQ
    Content-Type: text/plain; charset=windows-1252
    Content-Transfer-Encoding: quoted-printable

    There is no reason to keep the CentOS Kernel on your machines if the elrepo kernel is what you want to use.

    You should be able to (1) boot from an elrepo kernel then do:

    rpm -qa | grep kernel | sort

    then pick out the CentOS kernels and do:

    rpm -e

    where and are the name-version of the kernel you want to remove.

    Then you should not get updates for the CentOS Kernels, only for elrepo ones.

    The advice Jim gave you will then allow an update of ‘kernel-ml’ to actually update the grub.

    One thing to think about is that you need to update some other packages besides kernel to use the latest kernels on CentOS. These include xfsprogs, where without the new fsck.xfs, you can not properly fix errors in an xfs file system. See this bugL

    https://bugzilla.redhat.com/show_bug.cgi?id=1314605

    You can get a fairly updated kernel and xfsprogs (and a new supermin and some other packages here):

    http://mirror.CentOS.org/altarch/7/experimental/x86_64/Packages/

    You can exclude the kernel and just grab the xfsprogs if you want as well.

    My plan is to update that repo to the latest 4.4.x periodically while the 4.4 tree is in LTS. I will move that branch to another kernel once LTS 4.4 support stops.

    NOTE: I am not suggesting that kernel is better than any of the elrepo kernels, nor am I trying to compete with those kernels. I created this kernel for arm32 and i686 (and possibly aarch64) for the altarch SIGs so that we can support newer IoT products .. I also intend to build the x86_64 because we can and to give IoT users the ability to have the same kernel across several arches. I love elrepo and use it on several machines .. either choice is absolutely fine :)

    Thanks, Johnny Hughes

    –MqF2aGr7UI7UwlDvL6nQShnLUTJ8nhurQ

  • Well you might want to use kernel-ml by default and still get the CentOS
    kernels installed so you can test them when updates are released, and move back to them when they start supporting your hardware. In any case it does seem that DEFAULTKERNEL in /etc/sysconfig/kernel is not working as expected in C7. I’m pretty sure it worked in CentOS6.

LEAVE A COMMENT