Add more local storage (ephermal)

Hello Everyone, I have 4 physical drives on my server (1TB each) sda sdb sdc sdd

Ubuntu is installed on sda with the root and home directory mounted.

Under the openstack dashboard I see the available space to be 1TB (space of sda) We’re using ephermal storage to launch our instances.

sdb, sdc & sdd are added to a vg and is mounted How can I utilize this free space for ephermal storage? Please note that there are VMs running already and we would want to keep them.

The deployment environment single-node running on Ubuntu 20.04 setup via Microstack.