Single Chassis Topology - Brocade Communications Systems SilkWorm 12000 Design, Deployment And Management Manual

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SilkWorm 12000 Based SAN Designs
Figure 3-8 shows a method of using the SilkWorm 12000 on both the core and the edge of the fabric. It is
also possible to use Brocade 16-port products, such as the SilkWorm 2800 or 3800 at the edge. This
might be done if there are established16-port switches which can be reused for investment protection, or
if initial deployment cost needs to be kept at a minimum. In this way, it is theoretically possible to build
fabrics consisting of thousands of ports.
Figure 3-8 Using the SilkWorm 12000 As a Core and an Edge

Single Chassis Topology

With a single chassis it is possible to start with as few as 16-ports and expand to over 112-ports per
fabric. To achieve the highest availability, each SilkWorm 12000 chassis should participate in only one
fabric. To scale beyond 64 ports in a chassis, it is necessary to interconnect the two logical switches with
ISLs. If fabric port count requirements exceed 112 ports or if other switches will connect to the
SilkWorm 12000, then it is best to consider using a different topology.
If such expansion is expected, leave ports 12 through 15 open on the 16-port cards to enable expansion.
Because ports 12 through 15 are located on a single quad it is possible to use trunking when
interconnecting to other switches. For consistency, it is suggested to use the 16-port cards located in slots
one and two (logical switch 0) and slots seven and eight (logical switch 1) to support the interconnection
of logical switches within a SilkWorm 12000 chassis. As 16-port cards are added to the second logical
switch, interconnect the new 16-port cards by connecting to the additional 16-port cards. Connecting
each of the trunks to separate 16-port cards ensure connectivity between the two logical switches in the
event of an 16-port card failure. A fully configured SilkWorm 12000 that is connected by four 4 Gbit/sec
trunks yields 112-ports, a 7:1 ISL over subscription ratio, and is shown in Figure 3-9.
3-14 Publication Number 53-0000251-02