With every new kernel update, you receive another boot loader menu item. It will also eat up space from your /boot partition. If you don’t want your /boot partition to be filled up, then you need to remove some of the old kernels. How do we do it? First let’s get the list of kernels [...]

Responding to a ping request can not be the part of job definition for a production/critical server. For critical systems It is better not to publish information more than it is absolutely necessary. Disabling response to ICMP ECHO requests is a measure we can easily implement.

After doing a kernel upgrade, default kernel configuration in GRUB config will be automatically update. On Redhat based systems you can change this behavior by modifying /etc/sysconfig/kernel file. You need to set the UPDATEDEFAULT to no. UPDATEDEFAULT=no

If you have KVM kernel modules installed on your system then you would get following error message when you try to start VirtualBox. VirtualBox can’t operate in VMX root mode. Please disable the KVM kernel extension, recompile your kernel and reboot. VBox status code: -4011 (VERR_VMX_IN_VMX_ROOT_MODE). Result Code: 0×80004005 Component: Console Interface: IConsole {d5a1cbda-f5d7-4824-9afe-d640c94c7dcf} Solution [...]