What is /dev/mapper/vg_root-lv_root directory? Why my docker relies on this directory?
With below command, I managed to find which folder this drive maps to.
tree -LP 1 /dev/mapper/vg_os-lv_rootAfter that I was able to move folder to different drive (which have more space), in my case it was /var/lib/docker
You might have to install tree package using command yum install tree if not available by default.
Docker by design has a flaw OOB. It gets mounted on aufs by default. The better alternative to the same is to use Device mapper with lvm configured.
[https://docs.docker.com/engine/userguide/storagedriver/device-mapper-driver/#write-examples][1]
So in your case it seems you already have device mapper in place. So I suggest you create and extra loop-lvm config and add to your existing Volume Group based on the above documentation.