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NOTE: If you remove the hash algorithm configuration, the hash seed does not return to the original factory default setting.
To configure the hash algorithm seed, use the following command.
● Specify the hash algorithm seed.
CONFIGURATION mode.
hash-algorithm seed value [linecard slot-id] [port-set number]
The range is from 0 to 4095.
Link Bundle Monitoring
Link bundle monitoring allows the system to monitor the use of multiple links for an uneven distribution.
Monitoring linked ECMP bundles allows traffic distribution amounts in a link to be monitored for unfair distribution at any
given time. A global default threshold of 60% is Link bundle monitoring allows the system to monitor the use of multiple
links for an uneven distribution. . Links are monitored in 15-second intervals for three consecutive instances. Any deviation
within that time causes a syslog to be sent and an alarm event generate. When the deviation clears, another syslog is sent
and a clear alarm event generates. For example, link bundle monitoring percent threshold: %STKUNIT0-M:CP %IFMGR-5-
BUNDLE_UNEVEN_DISTRIBUTION: Found uneven distribution inECMP-GROUPbundle 11.
Example of Viewing Link Bundle Monitoring
DellEMC# show link-bundle-distribution ecmp-group 1
Link-bundle trigger threshold - 60
ECMP bundle - 1 Utilization[In Percent] - 44 Alarm State - Active
Interface Line Protocol Utilization[In Percent]
Te 1/1 Up 36
Te 1/1 Up 52
Managing ECMP Group Paths
To avoid path degeneration, configure the maximum number of paths for an ECMP route that the L3 CAM can hold. When you
do not configure the maximum number of routes, the CAM can hold a maximum ECMP per route.
To configure the maximum number of paths, use the following command.
NOTE:
For the new settings to take effect, save the new ECMP settings to the startup-config (write-mem) then reload
the system.
● Configure the maximum number of paths per ECMP group.
CONFIGURATION mode.
ip ecmp-group maximum-paths {2-64}
● Enable ECMP group path management.
CONFIGURATION mode.
ip ecmp-group path-fallback
DellEMC(conf)#ip ecmp-group maximum-paths 3
User configuration has been changed. Save the configuration and reload to take effect
DellEMC(conf)#
Creating an ECMP Group Bundle
Within each ECMP group, you can specify an interface.
If you enable monitoring for the ECMP group, the utilization calculation is performed when the average utilization of the
link-bundle (as opposed to a single link within the bundle) exceeds 60%.
1. Create a user-defined ECMP group bundle.
CONFIGURATION mode
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Equal Cost Multi-Path (ECMP)