Implementing And Monitoring Rib; Prerequisites For Implementing Rib; Information About Rib Configuration; Overview Of Rib - Cisco ASR 9000 Series Configuration Manual

Prerequisites for Implementing RIB

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Prerequisites for Implementing RIB
• You must be in a user group associated with a task group that includes the proper task IDs. The command
• RIB is distributed with the base Cisco IOS XR software; as such, it does not have any special requirements

Information About RIB Configuration

To implement the Cisco RIB feature, you must understand the following concepts:

Overview of RIB

Each routing protocol selects its own set of best routes and installs those routes and their attributes in RIB.
RIB stores these routes and selects the best ones from among all routing protocols. Those routes are downloaded
to the line cards for use in forwarding packets. The acronym RIB is used both to refer to RIB processes and
the collection of route data contained within RIB.
Within a protocol, routes are selected based on the metrics in use by that protocol. A protocol downloads its
best routes (lowest or tied metric) to RIB. RIB selects the best overall route by comparing the administrative
distance of the associated protocol.

RIB Data Structures in BGP and Other Protocols

RIB uses processes and maintains data structures distinct from other routing applications, such as Border
Gateway Protocol (BGP) and other unicast routing protocols, or multicast protocols, such as Protocol
Independent Multicast (PIM) or Multicast Source Discovery Protocol (MSDP). However, these routing
protocols use internal data structures similar to what RIB uses, and may internally refer to the data structures
as a RIB. For example, BGP routes are stored in the BGP RIB (BRIB), and multicast routes, computed by
multicast routing protocols such as PIM and MSDP, are stored in the Multicast RIB (MRIB). RIB processes
are not responsible for the BRIB and MRIB, which are handled by BGP and multicast processes, respectively.
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.1.x
426
BGP-RIB Feedback Mechanism for Update Generation, page 436
Configuration Examples for RIB Monitoring, page 436
Where to Go Next, page 439
Additional References, page 440
reference guides include the task IDs required for each command. If you suspect user group assignment
is preventing you from using a command, contact your AAA administrator for assistance.
for installation. The following are the requirements for base software installation:
◦ Router
◦ Cisco IOS XR software
◦ Base package

Implementing and Monitoring RIB

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