Specifications

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High Performance Trading/Algo Speed with Wombat Design and Implementation Guide
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Appendix B—Building and Configuring Switches
How will I identify my switches and hosts? You should create naming conventions that address the
following components:
• Rack names
• Host names
• Switch names
• Rack in which a given host resides
• Rack in which a given switch resides
In the event that the organization for which you are installing
the cluster already has established naming conventions,
defer to the existing rules. If you must invent conventions,
keep in mind the following options:
1. Name racks (e.g., Rack2, coreRack1, leafRack2).
2. Name core switches according to function and rack
location (e.g., R2C2, R5L1).
3. Name hosts according to rack location (R2slot3,
R3slot4)
Alternatively, name devices based on rack and IP addresses
(e.g. Rack2-125, where the IP address is 172.l68.0.125). In
these instances, apply IP addresses to the hosts in ascending
order as you go down the rack. Ideally, match IP addresses
to the rack (e.g., 172.168.4.x for Rack 4 and 172.168.5.x for
rack 5).
Create a topology map of your planned cluster. Create an
inventory of your planned cluster in a text file.
What devices will I connect with IB cables? Each host in the fabric connects to one leaf switch (if each
host is using one port). The switch and the hosts that
connect to the switch comprise a pod. Most commonly, 2 or
3 pods reside in each non-core rack.
Each leaf switch connects to every core switch. Cable the
same port on every leaf switch to the same core switch. (For
instance, every “port 24” on the leaf switches connect to the
same core switch.) Design symmetry into the network. If
possible, each leaf switch should have the same number of
connections to each core switch.
Do I run the embedded Subnet Manager or the Cisco
High-Performance Subnet Manager? How many backup
SMs do I run?
For any given fabric, you should configure a master subnet
manager with one backup subnet manager. The embedded
subnet manager that automatically arrives on all Cisco SFS
chassis cannot synchronize its database with the Cisco
High-Performance Subnet Manager. You must choose your
subnet management method before you begin to build your
fabric. Generally speaking, use the host-based SM for large
fabrics or fabrics using only large (144 – 288 port) switches
and the embedded SM for small fabrics (containing 7000
and/or 7008 switches). For details, refer to the
High-Performance Subnet Manager documentation.
Table 11 Planning Requirements (continued)