NOTE: While the seed is stored separately on each port-pipe, the same seed is used across all
CAMs.
NOTE: You cannot separate LAG and ECMP, but you can use different algorithms across the chassis
with the same seed. If LAG member ports span multiple port-pipes and line cards, set the seed to
the same value on each port-pipe to achieve deterministic behavior.
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.
A global default threshold of 60% is the usage percentage for the bundle; when the system reaches this
threshold, it begins monitoring the configured ECMP groups for uneven distribution. Links are monitored
in 15-second intervals for three consecutive instances. Any deviation exceeding 10% among any of the
bundle links sends a syslog and an alarm event is generated; for example, 01:16:25: %STKUNIT0-M:CP
%IFMGR-5-BUNDLE_UNEVEN_DISTRIBUTION: Found uneven distribution in ECMP-GROUP
bundle 1.
When the deviation clears, another syslog is sent and a clear alarm event is generated; for example,
01:35:14: %STKUNIT0-M:CP %IFMGR-5-BUNDLE_UNEVEN_DISTRIBUTION_ALARM_CLEAR: Uneven
distribution in ECMP-GROUP bundle 1 got cleared.
The link bundle utilization is calculated as the total bandwidth of all links divided by the total bytes-per-
second of all links, as shown in the following example.
Example of Viewing Link Bundle Monitoring
Dell# 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 0/0 Up 36
Te 0/1 Up 52

Managing ECMP Group Paths

To manage ECMP group paths, you can configure the maximum number of paths for an ECMP route that
the L3 CAM can hold to avoid path degeneration. 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.
340 Equal Cost Multi-Path (ECMP)