How Vsans Work; Chapter 11 Configuring And Managing Vsan - Cisco DS-C9216I-K9 Configuration Manual

How VSANs Work

How VSANs Work

A VSAN is a virtual storage area network (SAN). A SAN is a dedicated network that interconnects hosts
and storage devices primarily to exchange SCSI traffic. In SANs you use the physical links to make these
interconnections. A set of protocols run over the SAN to handle routing, naming, and zoning. You can
design multiple SANs with different topologies.
With the introduction of VSANs, the network administrator can build a single topology containing
switches, links, and one or more VSANs. Each VSAN in this topology has the same behavior and
property of a SAN. A VSAN has the following additional features:
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Figure 11-1
switches and the attached devices is independent of their segmentation into logical VSANs. Within each
VSAN, all members can talk to one another. Between VSANs no communication is possible.
Figure 11-1
Figure 11-2
2 (dashed) and VSAN 7 (solid). VSAN 2 includes hosts H1 and H2, application servers AS2 and AS3,
and storage arrays SA1 and SA4. VSAN 7 connects H3, AS1, SA2, and SA3.
Cisco MDS 9000 Fabric Manager Switch Configuration Guide
11-2
Multiple VSANs can share the same physical topology.
The same Fibre Channel IDs (FCIDs) can be assigned to a host in another VSAN, thus increasing
VSAN scalability.
Every instance of a VSAN runs all required protocols such as FSPF, domain manager, and zoning.
Fabric-related configurations in one VSAN do not affect the associated traffic in another VSAN.
Events causing traffic disruptions in one VSAN are contained within that VSAN and are not
propagated to other VSANs.
shows a fabric with three switches, one on each floor. The geographic location of the
Logical VSAN Segmentation
Engineering
VSAN
Switch 1
Switch 2
Switch 3
shows a physical Fibre Channel switching infrastructure with two defined VSANs: VSAN
Marketing Accounting
VSAN VSAN
Chapter 11 Configuring and Managing VSANs
Floor 3
Floor 2
Floor 1
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