Install LSI MegaCli package on Debian/Ubuntu/RedHat and Create 2 groups RAID5 for OVH Servers to use maximum disk space
Send your server to rescue mode, If you use rescue custom mode then you probably need to install megacli
Then you can, When your server reboots, log in to it via SSH using the rescue mode credentials that were emailed to you.
Install LSI MegaCli package on Linux - All distributions based on RedHat/Debian: