COMPUTING > Cloud Servers > Managing a Cloud Server > Kernel update for CentOS 6.x templates with Hyper-V

6.09 Kernel update for CentOS 6.x templates with Hyper-V Cloud Server Pro service guide

 ATTENTION: notes on System updates for CentOS 6.x Templates on Hyper-V platform.
In order to use all the potential offered by Hyper-V on CentOS Linux operating system you need to install the Microsoft "Linux Integration Services". Such components are specific for certain Kernel versions, therefore in case of an update of the latter, without the required precautions, problems could arise, such as "Kernel Panic" during boot which prevents the Cloud Server from starting correctly.

To get around this problem a rule has been added to the yum.conf file in order to exclude any new Kernels from updates made with yum command, therefore avoiding the above problems.

Should you need to update the Kernel, first of all you need to check that Microsoft has released a compatible version of the "Linux Integration Services" and if so proceed as follows:
  • Download the Linux Integration Services from, by specifying "integration services" in the search you will find the various versions that have been released.
  • Update the system, e.g.: yum update
    Attention: Do not Reboot the Cloud Server once the process has been completed.
  • Copy the downloaded file in the Cloud Server, usually a .iso file (to do this you can use the WinSCP utility).
  • Create a mount point, e.g.: mkdir /mnt/hvtools.
  • Mount the file, e.g.: mount -o loop LinuxICv34.iso /mnt/hvtools.
  • Check if there’s a previous version of the Integration Services, you can do this using the rpm -qa | grep microsoft command, if the output is null there are no installed versions, if the command gives you an output like the following:
    there is already a version of the Services installed.
  • Browse in the folder where you mounted the ISO file (for example /mnt/hvtools) using the command cd /mnt/hvtools:
    sh if there are no previous versions of the tools installed in the system,
    sh if there is a previous version installed in the system.
  • Once you have completed the installation reboot the Cloud Server.