Brocade Communications Systems LS-STK Installation Manual page 26

2
Preparing the installation site
In a linear stack topology there is a single stack cable connection between each device that carries
two-way communications across the stack. In a ring stack topology, an extra cable is connected
between the top and bottom devices forming a "ring" or "closed-loop." The closed-loop cable
provides a redundant path for the stack link, so if one link fails, stack communications can be
maintained.
You can build a stack containing up to 8 FastIron LS-STK units. Follow the steps below to connect
devices in a stack.
1. Plug one end of a stack cable into one of the CX4 stacking ports of the top unit.
2. Plug the other end of the stack cable into one of the stacking ports of the next unit.
3. Repeat steps 1 and 2 for each unit in the stack. Form a simple chain starting with a stacking
4. (Optional) To form a ring stack topology, plug one end of a stack cable into the remaining
TABLE 6
Data rate
9.95-10.3125
Gbps
NOTE: Average distance range is between 2 - 33 meters. Brocade recommends using the 2000 bandwidth
16
DRAFT: BROCADE CONFIDENTIAL
port on the top unit and ending at a stacking port on the bottom unit (stacking up to 8 units).
stacking port on the bottom unit and the other end into the remaining stacking port on the top
unit.
Use the .5 meter CX4 cables that shipped with each FLS-STK device to connect a linear stack
topology. For a ring topology, you will need an additional, longer (3.0 meter) CX4 cable.
NOTE
The total maximum stacking distance in linear and ring stack topologies is 1,000 meters
(3,281 feet). This length can consist of multiple inter-device stacking connections adding up to
1,000 meters. A single inter-device stacking connection should not exceed 1,000 meters.
Table 6 lists the recommended cable lengths for XFP cabling for various connection distances:
XFP optical link cable distances
Fiber type
62.5/125um MMF
62.5/1.25um MMF
50/125um MMF
50/123um MMF
50/125um MMF
version for distances greater than 80 meters.
Modal bandwidth @ Worst case distance range
850nm (Mhz-km) specified (m)
160 2 - 26
200 2 - 33
400 2 - 66
500 2 - 82
2000 2 - 300
Brocade FastIron LS and FastIron LS-STK Hardware Installation Guide
Typical range (m)
>400
53-1002187-01