Single-Tier Architecture Example - EMC Connectrix EC-1200 Planning Manual

Figure 4-15
Two-Tier Architecture
maintain a low hop count and low ISL load. Though many of the
industry's FC-SW device drivers can easily accommodate a move of a
Symmetrix port around the fabric, some device drivers require
server-level administrative changes, which complicates the
management of the single-tier environment.
The unstructured end result and the management load of moving
Symmetrix ports presents an advantage of moving to a two-tier
Symmetrix backbone architecture whenever the fabric is expected to
exceed four switches. If an existing environment has been built with
single-tier logical topologies, EMC Workload Analyzer can be used to
gauge the load on the Symmetrix ports and use this load to calculate
the ISL loading rate as the fabric is scaled to a larger number of
switches.
Server
Connectrix Connectrix
Connectrix Connectrix

Single-Tier Architecture Example

Two-tier architecture builds a Symmetrix backbone by centralizing all
the Symmetrix ports on one tier and locating all the server ports on
the second tier. The design produces a consistent one-hop
relationship between the servers and their Symmetrix ports. This
relationship is maintained as the fabric scales with more switches in
the server tier or the Symmetrix backbone tier. The current design
guideline advises one ISL between the server tier and the Symmetrix
backbone tier for every two fan-out groups. Tape ports, DWDM
ports, or longwave ports to a remote data center connect into the
Symmetrix backbone tier. RDF I/O on the Symmetrix backbone tier is
zero hops unless the RDF goes to a remote data center. If there are
Connectrix Version 6.02 Topology Solution Envelope
One fan-out group
repeated many times
x 8
on each switch
Symmetrix
Connectrix Topologies
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