Terminology; Troubleshooting Layer 3 Or Layer 4 Load Balancing - Cisco CRS-1 - Carrier Routing System Router Troubleshooting Manual

Chapter 13 Troubleshooting Load Balancing
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There is nothing to configure for Layer 2 load balancing. Active links in the bundle are automatically
eligible for load balancing.

Terminology

The following terms are applicable to load balancing.
Term
Prefix
Path
Session
Flow

Troubleshooting Layer 3 or Layer 4 Load Balancing

This section describes how to troubleshoot load balancing for Layer 3 or Layer 4 unicast flows when
Open Shortest Path First (OSPF) is the Interior Gateway Protocol (IGP).
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OL-21483-02
If all members have the same bandwidth, each is given relative weight of 1.
If all members happen to be OC768, each member receives a relative weight of 2, which balances
loads between two buffers.
Description
Describes a destination IP network, such as 192.16.10.0/24. Cisco IOS XR adds a
destination IP prefix to the routing table using information obtained from exchanging
messages using a dynamic routing protocol or by manual configuration of static routes.
Describes a valid route to reach a destination prefix. Cisco IOS XR assigns a cost to
each path. A set of active paths to a destination prefix may have equal or unequal costs.
Loads can be balanced across equal-cost paths.
Describes a unidirectional communication flow between two IP nodes. All packets in
a session use the same source and destination IP address.
A network flow is a unidirectional sequence of packets that common header fields,
which include the following:
Source IP address
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Destination IP address
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IP protocol
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Source port (for example UDP or TCP port)
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Destination port
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Ingress interface
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IP type of service
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Verifying the Routing Table Entries for Parallel Links
Configuring Layer 4 Load Balancing
Verifying the CEF Database and Measuring Flows
Troubleshooting Layer 3 or Layer 4 Load Balancing
Cisco IOS XR Troubleshooting Guide for the Cisco CRS-1 Router
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