Running the latest kernel RHEL, SL or CentOS

Using the ML kernel for my kvm host for performance gains on my kvm guests. You can easily install the ML or the LT kernels easily on CentOS7 using the ELrepo.

kernel-MT – mainline stable kernel
kernel-LT – long term support kernel


rpm –import
rpm -Uvh
yum remove kernel-headers kernel-tools kernel-tools-libs

edit /etc/yum.repos.d/elrepo.repo and enable=1 the elrepo-kernel. change the ml to lt to install the long term support kernel.

yum install kernel-ml.x86_64 kernel-ml-devel.x86_64 kernel-ml-headers.x86_64 kernel-ml-tools.x86_64 kernel-ml-tools-libs.x86_64 kernel-ml-tools-libs-devel.x86_64

time to get grub settled
awk -F' '$1=="menuentry " {print $2}' /etc/grub2.cfg

it should list all the kernels in grub2.cfg. if the first one is the newest kernel installed

grub2-set-default 0
grub2-mkconfig -o /boot/grub2/grub.cfg

REBOOT and you will be running the latest kerne


Activate windows when not connected to the internet

1. To Change Product Key Number in a Command Prompt Open an elevated command prompt. In the elevated command prompt, type in the command below and press enter.

NOTE: Substitute XXXXX-XXXXX-XXXXX-XXXXX-XXXXX in this command below with your actual product key number with dashes instead.


2. Type slui.exe 4 to access the phone activation screen and follow the steps to activate over the phone.