I am coming from HP-UX and delighted that all the LVM commands are nearly identical to the HP LVM version. This is what I have installed, not sure which version I am running out of these. But vgdisplay, lvdisplay, etc. all work. And I really like some of the options to lvextend how you can allocate the remaining disk to a partion, a cool feature.

Any other fans that love LVM?

oot@ngrca4-mup:/var/tmp# yum list installed | grep -i lvm
lvm2.x86_64 2.02.143-12.el6_9.1 @RHEL6patch
lvm2-libs.x86_64 2.02.143-12.el6_9.1 @RHEL6patch
mesa-private-llvm.x86_64 3.6.2-1.el6 @anaconda-RedHatEnterpriseLinux-201604140956.x86_64/6.8

There are a few - many (home) users consider it overkill and overly complex. I took a few years to be convinced, but recent releases have better integration of RAID and automatic recovery to spare devices.
Redhat have excellent docs online - including an LVM Admin guide.

LVM is the standard for enterprise environments, with Veritas being the other popular choice.

It makes managing terabytes of data much easier. When you have Oracle and other apps running. It's highly dynamic.

Maybe not needed when you can build a fixed size filesystem for personal use and never shrink it or grow it.

With RH Enterprise increasingly invading the corporate arena, knowledge of LVM is critical for Linux systems administrators since they not manage a static system with a fixed number of TB or GB without any SAN involved.

And there are performance issues. Mirroring, striping - and resizing (both up and down) are all essential tasks. The command set is actually very simple.