My Proxmox installation has 4 HD's. I cannot figure out how to add the 3 additional drives to allow for their use. I have followed the link below, but I suppose I must be too much of a NOOB to be able to figure it out. I have some experience with ESXi and was able to manage there, but this is more complicated. I have found several other answers to this question, but often times they are many years old. Thanks in advance for the help.
http://pve.proxmox.com/wiki/Storage_Model#LVM_Groups_with_Local_Backing
http://pve.proxmox.com/wiki/Storage_Model#LVM_Groups_with_Local_Backing