Command Line Reference Guide

• hash-algorithm linecard 2 ip-sa-mask 00 ip-da-mask aa
The different hash algorithms are based on the number of Port Channel members
and packet values. The default hash algorithm (number 0) yields the most balanced
results in various test scenarios, but if the default algorithm does not provide a
satisfactory distribution of traffic, use the hash-algorithm command to designate
another algorithm.
When a Port Channel member leaves or is added to the Port Channel, the hash
algorithm is recalculated to balance traffic across the members.
On TeraScale, if you do not enter the keyword ECMP or LAG, the Dell Networking
OS assumes it to be common for both. If the keyword ECMP or LAG is entered
separately, both should fall in the range of 0 to 23 or 24 to 47 since compression
enable/disable is common for bothTeraScale and ExaScale support the range 0-47.
The default for ExaScale is
24.
hash-algorithm ecmp
Change the hash algorithm used to distribute traffic flows across an ECMP (equal-cost multipath routing)
group.
Syntax
hash-algorithm ecmp {crc-upper} | {dest-ip} | {lsb}
To return to the default hash algorithm, use the no hash-algorithm ecmp
command.
Parameters
crc-upper Uses the upper 32 bits of the key for the hash computation.
The default is crc-lower.
dest-ip Uses the destination IP for ECMP hashing. The default is
enabled.
lsb Returns the LSB of the key as the hash. The default is crc-
lower.
Defaults
• crc-lower
• dest-ip enabled
Command
Modes
CONFIGURATION
Command
History
Version 9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
The hash value calculated with the hash-algorithm command is unique to the
entire chassis. The default ECMP hash configuration is crc-lower. This command
takes the lower 32 bits of the hash key to compute the egress port and is the “fall-
back” configuration if you have not configured anything else.
506
Equal Cost Multi-Path (ECMP)