Use LVM if you have single disk.

# List disk devices with lsblk
# Select a device to add
# create partions
$ fdisk /dev/sdb
 
# format device
$ mkfs.ext4 /dev/sdb1
 
# Create a physical group
$ pvcreate /dev/sdb1
 
# Create logical group
$ vgcreate vSSD /dev/sdb1
 
# TO add DataCenter -> Storage -> Add -> LVM
 
---
 
# To add as a dir
# After formatting mount the some dir
$ mkdir /backup
$ mount /dev/sdb1 /backup
$ vim /etc/fstab
/dev/sdb1/ /backup ext4 defaults 0 0
 
# To add Datacenter -> Storage -> Add -> Directory