How to update Kernel version on Centos 7

To update latest kernel version on Centos 7

Linux kernel is one of the largest open source project with upgrading versions. Updating the latest kernel version on Centos 7 is explained in this manual.

Check the current kernel version using the following command.

[root@linuxhelp ~]# uname -r
3.10.0-123.el7.x86_64

Add the EPEL GPG key to enable the EPEL repository and EPEL repo fastest mirror using the below command.

[root@linuxhelp ~]# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org

Before installation process enable the epel repo using following command.

[root@linuxhelp ~]# rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
Retrieving http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
Preparing...                          ################################# [100%]
Updating / installing...
   1:elrepo-release-7.0-2.el7.elrepo  ################################# [100%]

Now enable the epel repo’ s fastest mirror using below command.

[root@linuxhelp ~]# yum install yum-plugin-fastestmirror -y
Loaded plugins: fastestmirror, langpacks
Determining fastest mirrors
 * base: centos.webwerks.com
 * elrepo: mirrors.thzhost.com
 * extras: centos.webwerks.com
 * updates: centos.webwerks.com
Resolving Dependencies
-->  Running transaction check
--->  Package yum-plugin-fastestmirror.noarch 0:1.1.31-24.el7 will be updated
--->  Package yum-plugin-fastestmirror.noarch 0:1.1.31-34.el7 will be an update
-->  Finished Dependency Resolution
.
.
.
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
Importing GPG key 0xF4A80EB5:
 Userid     : " CentOS-7 Key (CentOS 7 Official Signing Key) < security@centos.org> " 
 Fingerprint: 6341 ab27 53d7 8a78 a7c2 7bb1 24c6 a8a7 f4a8 0eb5
 Package    : centos-release-7-0.1406.el7.centos.2.3.x86_64 (@anaconda)
 From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Warning: RPMDB altered outside of yum.
  Updating   : yum-plugin-fastestmirror-1.1.31-34.el7.noarch                                                                                                                   1/2 
  Cleanup    : yum-plugin-fastestmirror-1.1.31-24.el7.noarch                                                                                                                   2/2 
  Verifying  : yum-plugin-fastestmirror-1.1.31-34.el7.noarch                                                                                                                   1/2 
  Verifying  : yum-plugin-fastestmirror-1.1.31-24.el7.noarch                                                                                                                   2/2 

Updated:
  yum-plugin-fastestmirror.noarch 0:1.1.31-34.el7                                                                                                                                  

Complete!

Start to install the latest kernel version.

[root@linuxhelp ~]# yum --enablerepo=elrepo-kernel install kernel-ml -y
Loaded plugins: fastestmirror, langpacks 
Loading mirror speeds from cached hostfile
 * base: centos.webwerks.com
 * elrepo: mirrors.thzhost.com
 * elrepo-kernel: mirrors.thzhost.com
 * extras: centos.webwerks.com
 * updates: centos.webwerks.com
Resolving Dependencies
-->  Running transaction check
--->  Package kernel-ml.x86_64 0:4.7.0-1.el7.elrepo will be installed
-->  Finished Dependency Resolution
.
.
.
Downloading packages:
kernel-ml-4.7.0-1.el7.elrepo.x86_64.rpm                                                                                                                     |  39 MB  00:09:12     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : kernel-ml-4.7.0-1.el7.elrepo.x86_64                                                                                                                             1/1 
  Verifying  : kernel-ml-4.7.0-1.el7.elrepo.x86_64                                                                                                                             1/1 

Installed:
  kernel-ml.x86_64 0:4.7.0-1.el7.elrepo                                                                                                                                            

Complete!

After the installation completes, reboot the system to use newer kernel version using the following command.

[root@linuxhelp ~]# uname -r
4.7.0-1.el7.elrepo.x86_64