Users Guide

Dell provides a CLI-based solution for modifying the hash seed to ensure that on each configured
system, the ECMP selection is same. When configured, the same seed is set for ECMP, LAG, and NH, and
is used for incoming traffic only.
NOTE: While the seed is stored separately on each port-pipe, the same seed is used across all
CAMs.
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.
If the hash algorithm configuration is removed, the hash seed does not go to the original factory
default setting.
ip ecmp-group
Enable and specify the maximum number of ecmp that the L3 CAM hold for a route, By default, when maximum paths are not
configured, the CAM can hold a maximum of 16 ecmp per route.
S4820T
Syntax
ip ecmp-group {maximum-paths | {number} {path-fallback}
To negate a command, use the no ip ecmp-group maximum-paths {number} command.
Parameters
maximum-paths Specify the maximum number of ECMP for a route. The range is 2 to 64.
path-fallback Use the keywords path-fallback to enable this feature. If you enable the
feature, re-enter this keyword to disable the feature.
Defaults 16
Command Modes CONFIGURATION
Command History
This guide is platform-specific. For command information about other platforms, see the relevant Dell
Networking OS Command Line Reference Guide.
Version Description
9.8(1.0) Introduced on the Z9100–ON.
9.8(0.0P5) Introduced on the S4048-ON.
9.8(0.0P2) Introduced on the S3048-ON.
9.7(0.0) Introduced on the S6000-ON.
9.2(1.0) Introduced on the Z9500.
9.0.2.0 Introduced on the S6000.
9.0.0.0 Introduced on the Z9000.
8.3.10.0 Introduced on the S4810.
Usage Information You must save the new ECMP settings to the startup-config (write-mem) then reload the system for the
new settings to take effect.
Equal Cost Multi-Path (ECMP) 591