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Dell EMC PowerVault ME4 Series and Citrix XenServer | H18237
3 XenServer storage overview
XenServer environments utilize shared storage as part of the virtualization platform. Shared storage can be
connected through iSCSI, Fibre Channel (FC), SAS or NFS. The information contained in this document is
focused on iSCSI block storage connectivity because the Dell EMC PowerVault ME4 Series storage platform is a
block storage platform.
Block storage devices in the form of iSCSI or FC LUNs are presented to the XenServer hosts, from which
SRs are created. SRs, which are connected to all XenServer hosts participating in the XenServer pool, are
the entity on which VDIs reside. VDIs are recognized by VMs as physical disks and are persistent on the SRs.
3.1 Shared iSCSI storage
XenServer using Dell EMC PowerVault ME4 Series storage provides support for shared SRs on iSCSI-
attached LUNs. iSCSI LUNs can use the Open-iSCSI software initiator or a supported iSCSI host bus
adapter (HBA). Figure 2 and Figure 3 illustrate how both the Open-iSCSI software initiator and iSCSI HBA
environments look conceptually.
Figure 2: Shared iSCSI storage using the Open-iSCSI software initiator