Storage+Compute: Existing Cisco HyperFlex clusters can be expanded by adding additional HX nodes, which adds additional compute and storage resources to the shared pool.
Compute-only: The IO Visor module is a vSphere Installation Bundle (VIB) that provides a network file system (NFS) mount point so that the ESXi hypervisor can access the virtual disk drives that are attached to individual virtual machines. From the hypervisor’s perspective, it is simply attached to a network file system.
The IO Visor module is installed on each storage node as well as each compute-only node in order to allow fast access the to the HX distributed file system (LogFS). Up to 8 hybrid or 16 all-flash Cisco UCS B2x0/B4x0/C2x0/C4x0 nodes can accomodate a compute-only role within a single storage cluster.
Storage-only: N/A; A Cisco HyperFlex node always takes active part in the hypervisor (compute) cluster as well as the storage cluster.
Cisco HyperFlex Edge: The initial configuration cannot be expanded beyond the default configuration, which consists of 3 HX220x Edge M5 rack-servers.