ServerNet Cluster 6780 Planning and Installation Guide (G06.28+, H06.05+)

Table Of Contents
Using the Long-Distance Option
ServerNet Cluster 6780 Planning and Installation Guide527301-005
G-6
Bandwidth Considerations
lengths outside this range can degrade cluster performance and cause severe errors
that result in a loss of ServerNet connectivity between nodes.
Bandwidth Considerations
With the long-distance option, overall bandwidth is reduced due to end-to-end
transmission latency and lower link transmission rates. Depending on your application
profile, this limit might affect cluster performance.
Although each 6780 switch can support up to eight nodes, you should consider the
number of processors supported by each long-distance link between the switches. To
ensure adequate throughput, under conditions of heavy traffic, each link should
support no more than 12 processors. Using all four links between the switches, this
guideline equates to no more than 48 processors for each 6780 switch, regardless of
the number of nodes.
If one of the four links goes down, the other links must handle the traffic for both the
down link and themselves (an additional 12 processors worth of traffic). An OSM alarm
and EMS events are generated when the link is down. If the bad link remains down, it
must be repaired to regain the lost bandwidth.
Installation Considerations
In general, you can follow the planning, preparation, and installation procedures
described in the main part of this manual to set up a long-distance configuration.
This subsection describes areas where the long-distance installation differs from the
general procedures. Also, throughout the manual, notes have been provided when you
need to be aware of long-distance issues.
Software Installation
For guidance in installing the software, refer to Installing the Server Software on
page 4-4. However, be sure you install the software listed in Table G-1 on page G-4.
To load the firmware and configuration images to the 6780 switches, refer to
Appendix F, Updating the 6780 Switch Logic Board Firmware, Configuration, and
FPGA Images. Be sure to load the versions listed in Table G-1 on page G-4.
Hardware Installation
To install the 6780 switches, follow the procedures in Section 5, Installing 6780
Switches but note the different requirements for the numeric selector settings and
zone-to-zone connections.
Note. The long-distance option does not affect the supported lengths for layer-to-layer
connections and switch-to-node connections.