Install the default Kernel on CentOS 7 images

All the images we offer at Clouding.io are built by us, and we adapt them to work 100% with our platform. This is why we need to make a number of additional configurations for certain operating system aspects.

Because of these changes, installing certain software from the accounts may produce some kind of error because a different kernel version was expected. We use a kernel that is newer than the distribution's own kernel. To return to the previous kernel (and the distribution's official one), you need to downgrade the kernel to version 3.10.

The first step is to enable the base repo for CentOS:

# vi /etc/yum.repos.d/CentOS-Base.repo

And at the very end, add the following:

enabled=1

Then move the repo for Clouding:

# mv /etc/yum.repos.d/CentOS-clouding.repo /etc/yum.repos.d/CentOS-clouding.disable

Update the repo and clear the cache:

# yum update
# yum clear all
# rm -rf /var/cache/yum

Then install the following packages:

# yum install kernel-devel kernel

Now restart the server, go to the Consola VNC and select kernel 3.10. Now, if you run uname -r, it should display: 3.10.0-693.el7.x86_64

Then remove kernel 3.14:

# yum remove kernel-3.14.43_1-2.x86_64 kernel-devel-3.14.43_1-2.x86_6 kernel-headers-3.14.43_1-2.x86_64

Finally, update Grub:

# grub2-mkconfig -o /etc/grub2.cfg

From now on, our Centos 7 image will always boot with kernel 3.10.0, and we will be able to compile or install the software we need.