How to create LVM with four disks on CentOS 7 linux

In this article we will show you how to create LVM with four disks on CentOS 7 linux.
As you may know, LVM is like "dynamic partitions", meaning that you can create/resize/delete LVM "partitions" (they're called "Logical Volumes" in LVM-speak) from the command line while your Linux system is running: no need to reboot the system to make the kernel aware of the newly-created or resized partitions.