I run a web hosting service and have extensive server experience, so I can safely grow your linux disk to include additional space.
Please note that if you have added another disk, not more disk space to your existing setup, it will need to be added as a directory. Your best bet is to ensure disk SPACE has been added, not another separate disk.
Data should be backed up prior to job being started. I will use any existing OVH backup system to do so.