Configuration Guidelines And Requirements; Pci Buses And Port Adapter And I/O Controller Architecture - Cisco 7206VXR - VPN Bundle Router Supplementary Manual

Configuration Guidelines and Requirements

The Cisco 7200 series routers do not support a mix of installed AC-input and DC-input power
Note
supplies.
AC-input power supply. (A power supply filler plate is installed over the second power supply bay.)
Three internal fans draw cooling air into the chassis interior and across internal components to maintain
an acceptable operating temperature (see
in the subchassis.
The I/O controller, port adapters, Port Adapter Jacket Card, power supplies, and NPE or NSE slide into
their respective chassis slots and connect directly to the router midplane; there are no internal cables to
connect.
Configuration Guidelines and Requirements
Understanding the relationship between the three Peripheral Component Interconnect (PCI) buses, I/O
controller, and port adapters is important in understanding the rationale for the bandwidth point
information that is provided in this document.

PCI Buses and Port Adapter and I/O Controller Architecture

All port adapters and service adapters installed in Cisco 7200 series routers connect to one of two
Peripheral Component Interconnect (PCI) buses, mb1(left bus) or mb2 (right bus), on the router
midplane that provide a path to packet I/O memory and the system (routing and switching) processor.
The optional ports on the I/O controller connect to a third PCI bus, mb0 (left bus), that connects to one
of the PCI buses or to both of the PCI buses, depending on which network processing engine (NPE) or
network services engine (NSE) is installed and supported in your system.
With an NPE-G1 or NPE-G2 installed, the I/O controller connects on the third PCI bus, mb0, which
connects directly into the NPE-G1 or NPE-G2. When installed with the NPE-G1 or NPE-G2, the I/O
controller does not take bandwidth from the two PCI buses (left and right) dedicated to the port adapters.
The Port Adapter Jacket Card, for use in the Cisco 7200 VXR routers and only with the NPE-G1 or
NPE-G2, installs in the I/O controller slot on PCI bus mb0. Because the Port Adapter Jacket Card accepts
only one port adapter, and the PCI bus provides another 600 bandwidth points, this bus cannot be
oversubscribed because no port adapter is assigned more than 600 bandwidth points.
Guidelines for distributing the port adapters evenly between the two buses are given in the
for Installation" section on page
Cisco 7200 Series Port Adapter Hardware Configuration Guidelines
1-4
Figure 1-2 shows the rear of a Cisco 7200 series router configured with a single 280W
1-6.
Chapter 1 Cisco 7200 Series Port Adapter Installation Requirements
Figure 1-2). The three fans are enclosed in a tray that is located
"Guidelines
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