Chapter 14: Monitoring the Routing Engine
Understanding the Routing Engine
Purpose Inspect the Routing Engine to ensure that key system processes are operating normally.
What Is a Routing
Engine
The Routing Engine is a key component in the router. It is primarily responsible for the protocol intelligence of the router. Thus, it is responsible for creating a routing table, which consists of all routes learned by all protocols running on the router.
The Routing Engine interprets the routing table, generates a subset of routes to be used for all forwarding purposes, and places them in the forwarding table. The
Routing Engine also holds the microcode for the Packet Forwarding Engine.
The Routing Engine is responsible for user interaction functions, such as the command-line interface (CLI), Simple Network Management Protocol (SNMP) management, and craft interface interaction.
The Routing Engine consists of the following components:
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Intel Pentium compact Peripheral Component Interconnect (PCI) platform
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Nonrotating compact flash drive (RAM disk)
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Standard rotating hard drive
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Removable media drive
The JUNOS software resides on the compact flash drive, with an alternate copy residing on the system hard drive.
This section also includes the following information:
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Routing Engine Types and Characteristics on page 127
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Routing Engine Locations on page 130
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Routing Engine Redundancy on page 135
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Routing Engine Component Companionship on page 135
Routing Engine Types and Characteristics
This section lists the Routing Engine characteristics that are supported in each routing platform. It also shows the Routing Engine component supported in each routing platform. This section covers the following routing platforms:
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M7i and M10i Router Routing Engine on page 128
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M5, M10, M20, M40, M40e, and M160 Router Routing Engines on page 129
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M320 Router Routing Engine on page 129
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T320 Router and T640 Routing Node Routing Engine on page 130
Understanding the Routing Engine !
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