Cisco ASR 900 Series User Manual

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Smaller path minimum bandwidth
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Smaller hop count value
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Lexicographically selects a smaller path bandwidth vector (bandwidth value is sorted in ascending order)
Tie-breaker 3: random
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Smaller path cost value
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Smaller hop count value
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Randomly selects a path regardless of the path bandwidth value (as long as it satisfies the request
constraints)
The key decision criterion is still path cost; the tie-breakers evaluate, in sequence, until a path is selected. The
random tie-breaker does not take the available link bandwidth into consideration.
Configuring Flex LSP ECMP min-fill and max-fill
ECMP can be configured globally or specifically to a tunnel. Tunnel specific configuration override the global
tiebreaker selection. The default selection algorithm is min-fill.
For a Flex LSP co-routed tunnel, the same path-selection tiebreaker should be configured on each end of the
bi-directional LSP.
Global Configuration Command
Router(config)# mpls traffic-eng path-selection tiebreaker ?
max-fill Use max-fill tiebreaker
min-fill Use min-fill tiebreaker
random Use random tiebreaker
Use the no mpls traffic-eng path-selection tiebreaker command to remove the global configuration.
Tunnel-Specific Configuration Commands
Configure path selection tiebreaker that is applicable to a specific tunnel. Tunnel specific configuration override
global tiebreaker configuration.
Router(config)# interface tunnel 1400
Router(config-if)# tunnel mpls traffic-eng path-selection tiebreaker ?
max-fill Use max-fill tiebreaker
min-fill Use min-fill tiebreaker
random Use random tiebreaker
Use the no tunnel mpls traffic-eng path-selection tiebreaker command to remove the tunnel-specific
configuration.
Router(config)# interface tunnel 2000
Router(config-if)# ip unnumbered loopback0
Router(config-if)# tunnel mode mpls traffic-eng
Router(config-if)# tunnel destination 56.6.6.6
Router(config-if)# tunnel mpls traffic-eng bidir association type co-routed fault-oam wrap
Router(config-if)# tunnel mpls traffic-eng bidir association id 2000 source 55.5.5.5 global
2000
Router(config-if)# tunnel mpls traffic-eng path-select tie min-fill
Router(config-if)# tunnel mpls traffic-eng bandwidth 5000
Router(config-if)# tunnel mpls traffic-eng autoroute announce
Router(config-if)# tunnel mpls traffic-eng path-option 10 dynamic
Router(config)# interface tunnel 2000
Router(config-if)# ip unnumbered loopback0
Router(config-if)# tunnel mode mpls traffic-eng
Router(config-if)# tunnel destination 56.6.6.6
Router(config-if)# tunnel mpls traffic-eng bidir association type co-routed fault-oam wrap
Router(config-if)# tunnel mpls traffic-eng bidir association id 2000 source 55.5.5.5 global
2000
MPLS Basic Configuration Guide, Cisco IOS XE Everest 16.5.1 (Cisco ASR 900 Series)
162
Flex LSP Overview
Flex LSP ECMP min-fill, max-fill, random

Cisco ASR 900 Series Specifications

General

Brand	Cisco
Model	ASR 900 Series
Category	Network Router
Language	English