Cisco Cisco IOS Software Release 12.0(21)S
Per-Packet Load Balancing
Configuration Tasks
3
Cisco IOS Release: Multiple releases (see the Feature History table)
Benefits
Avoid Path Congestion
Per-packet load balancing avoids overloading by spreading traffic for a given destination across different
network links.
network links.
Improve Path Utilization
Data traffic is balanced over multiple links.
Restrictions
Out-of-Sequence Packets
Using per-packet load balancing to share the traffic load across available paths to a given destination can
cause out-of-sequence packets in a particular data flow. This can result in unsatisfactory data
transmission for video and voice streaming.
cause out-of-sequence packets in a particular data flow. This can result in unsatisfactory data
transmission for video and voice streaming.
Configuring Load Balancing in the Same Way on All E2 Line Cards
You must globally configure load balancing on E2 line cards so that it is performed either in
per-destination or per-packet mode. It is not possible (as in other Cisco IOS software-based platforms)
to configure some packet prefixes in per-destination mode and others in per-packet mode. Although you
could configure one E2 line card in one load balancing mode and all other E2 line cards in the other
mode, this would not be practical and would result in a limited use of the router. For this reason, Cisco
recommends that you configure load balancing on all E2 line cards in the 12000 Series Internet Router
in the same way: either per-packet or per-destination.
per-destination or per-packet mode. It is not possible (as in other Cisco IOS software-based platforms)
to configure some packet prefixes in per-destination mode and others in per-packet mode. Although you
could configure one E2 line card in one load balancing mode and all other E2 line cards in the other
mode, this would not be practical and would result in a limited use of the router. For this reason, Cisco
recommends that you configure load balancing on all E2 line cards in the 12000 Series Internet Router
in the same way: either per-packet or per-destination.
Related Features and Technologies
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Cisco Express Forwarding
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Multiprotocol Label Switching (MPLS)
•
NetFlow services
Configuration Tasks
See the following sections for configuration tasks for the Per-Packet Load Balancing feature. Each task
in the list is identified as either required or optional:
in the list is identified as either required or optional:
•
(required)
•
(optional)
•
(required)