By using Hosted SAN can rent disk storage per GB on a storage area network. All storage area network has dual RAID controller and dual power supply.
You can choose to use storage on SSD drives, SATA or SAS disks and between ISCSI (10 GB), SAS (12 GB) or fiber channel (16 GB) interface.
It is also possible to combine the different techniques on a single server. You can for example choose to have a 10Gb iSCSI SATA partition as a cluster witness (quorum) and a 16 GB Fibre Chanell partion for MS SQL databases.
You can also get ISCSI disks to virtual machines, enabling clustring between two virtual hosts.