Citrix Hypervisor data stores are called Storage Repositories (SRs), they support IDE, SATA, SCSI (physical HBA as well as SW initiator) and SAS drives locally connected, and iSCSI, NFS, SMB, SAS and Fibre Channel remotely connected.
Background: The SR and VDI abstractions allow for advanced storage features to be exposed on storage targets that support them. For example, advanced features such as thin provisioning, VDI snapshots, and fast cloning. For storage subsystems that don’t support advanced operations directly, a software stack that implements these features is provided. This software stack is based on Microsoft’s Virtual Hard Disk (VHD) specification.
SR commands provide operations for creating, destroying, resizing, cloning, connecting and discovering the individual VDIs that they contain.
Reference: https://tinyurl.com/y222m23o
Also refer to the XenServer Hardware Compatibility List (HCL) for more details.