This is so helpful if you are trying to extend a partition on a Linux machine hosted on Hyper V. You do have to reboot before pvcreate /dev/hda?. That detail is missing.
If you are new to linux this might be a little difficult. Once you have some basics nailed, its super easy. Here’s how to get it working without worrying about usergroups etc etc. I just wanted to get it working with my WordPress setup (Apache).
"Under Linux there are GUIs (graphical user interfaces), where you can point and click and drag, and hopefully get work done without first reading lots of documentation. The traditional Unix environment is a CLI (command line interface), where you type commands to tell the computer what to do. That is faster and more powerful, but requires finding out what the commands are."
-- from man intro(1)