Cisco Systems 9000 Manual De Usuario

Descargar
Página de 282
 
1-15
Cisco ASR 9000 Series Aggregation Services Router Hardware Installation Guide
Chapter 1      Preparing for Installation
Site Requirement Guidelines
Site Wiring Guidelines
When planning the location of the router, consider distance limitations for signaling, electromagnetic 
interference (EMI), and connector compatibility. If the wiring is run for any significant distance in an 
electromagnetic field, interference can occur between the field and the signals on the wires. Poor wiring 
can cause:
Radio interference emanating from the wires.
Strong EMI, especially when caused by lightning or radio transmitters. EMI can destroy the signal 
drivers and receivers in the router, and can even create an electrical hazard by conducting power 
surges through lines and into equipment.
Note
To predict and remedy strong EMI, you may need to consult with experts in radio frequency 
interference (RFI).
Site wiring is unlikely to emit radio interference if you use twisted-pair cable with a good distribution 
of grounding conductors. Use a high-quality twisted-pair cable with one ground conductor for each data 
signal, when applicable.
Give special consideration to the effect of a lightning strike in your vicinity, especially if the wiring 
exceeds the recommended distances, or if it passes between buildings. The electromagnetic pulse (EMP) 
caused by lightning or other high-energy phenomena can easily induce enough energy into unshielded 
conductors to destroy electronic devices. If you have experienced EMP problems in the past, you may 
want to consult experts in electrical surge suppression and shielding.
Most data centers cannot resolve infrequent but potentially catastrophic problems without pulse meters 
and other special equipment. In addition, these problems can take a great deal of time to identify and 
resolve. We recommend that you take the necessary precautions to avoid these problems by providing a 
properly grounded and shielded environment, with special attention to issues of electrical surge 
suppression.
Chassis Air Flow Guidelines
 describes how cool air is circulated through the Cisco ASR 9000 Series Routers.
Table 1-1
Chassis Air Flow Guidelines
Router Type
Chassis Air Flow 
Cisco  ASR  9010
Air is circulated by two fan trays located underneath the Route Switch Processor 
(RSP) and line cards as shown in 
.
Cisco ASR 9006
Air is circulated by two fan trays located along the top left side above the RSP 
and line cards as shown in 
Cisco ASR 9904
 
Air is circulated side-to-side by a single fan tray located along the left side of 
the chassis as shown in 
If the router is installed in a 2-post 23-inch rack, air flow is circulated 
front-to-back. Optionally, you can install air baffles on the chassis to help 
isolate the exhaust air from the intake air. For more information, see 
.