Juniper MX480, Руководство по оборудованию

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•
Routing Engine Specifications on page 70
• Supported Routing Engines by Router on page 74
MX480 Host Subsystem Description
The host subsystem provides the routing and system management functions of the
router. You can install one or two host subsystems on the router. Each host subsystem
functions as a unit; the Routing Engine must be installed directly into the Switch Control
Board.
NOTE: We recommend that you install two host subsystems for redundant
protection. If you install only one host subsystem, we recommend that you
install it in slot
0
.
Each host subsystem has three LEDs that display its status. The host subsystem LEDs
are located in the middle of the craft interface.
See Also Maintaining the MX480 Host Subsystem on page 240
•
•
Taking an MX480 Host Subsystem Offline
MX480 Host Subsystem LEDs
Each host subsystem has three LEDs that display its status. The host subsystem LEDs
are located on the upper left of the craft interface. For more information, see
“Host
Subsystem LEDs on the MX480 Craft Interface” on page 38 .
MX480 Midplane Description
The midplane is located toward the rear of the chassis and forms the rear of the card
cage (see
Figure 18 on page 60 ). The line cards and SCBs install into the midplane from
the front of the chassis, and the power supplies install into the midplane from the rear
of the chassis. The cooling system components also connect to the midplane.
The midplane performs the following major functions:
• Data path—Data packets are transferred across the midplane between the line cards
through the fabric ASICs on the SCBs.
•
Power distribution—The router power supplies connect to the midplane, which
distributes power to all the router components.
• Signal path—The midplane provides the signal path to the line cards, SCBs, Routing
Engines, and other system components for monitoring and control of the system.
59 Copyright © 2019, Juniper Networks, Inc.
Chapter 1: Overview