Administrator Guide

Term heading Description heading
The following is a list of the Dell Networking OS version history for this command.
Version Description
8.3.19.0 Introduced on the S4820T.
8.3.11.1 Introduced on the Z9000.
8.3.7.0 Introduced on the S4810.
8.1.1.0 Introduced on the E-Series ExaScale.
7.6.1.0 Introduced on the S-Series.
7.5.1.0 Introduced on the C-Series.
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.
The different hash algorithms are based on the number of ECMP group members and packet values.
The default hash algorithm yields the most balanced results in various test scenarios, but if the default
algorithm does not provide satisfactory distribution of traffic, use this command to designate another
algorithm.
When a member leaves or is added to the ECMP group, the hash algorithm is recalculated to balance
traffic across the members.
hash-algorithm hg
To distribute traffic flows across different internal HiGig links, change the hash algorithm.
Z9000
Syntax
hash-algorithm hg {crc16 | xor1 | xor2 | xor4 | xor8 | xor16 | crc16cc |
crc32MSB | crc32LSB} stack-unit number port-set number
Parameters
crc16 Use CRC16_BISYNC — 16 bit CRC16-bisync polynomial (default).
xor1 Use CRC16_BISYNC_AND_XOR1 — Upper 8 bits of CRC16-BISYNC and lower 8
bits of xor1.
xor2 Use CRC16_BISYNC_AND_XOR2 — Upper 8 bits of CRC16-BISYNC and lower 8
bits of xor2.
xor4 Use CRC16_BISYNC_AND_XOR4 — Upper 8 bits of CRC16-BISYNC and lower 8
bits of xor4.
xor8 Use CRC16_BISYNC_AND_XOR8 — Upper 8 bits of CRC16-BISYNC and lower 8
bits of xor8.
xor16 Use CR16 — 16 bit XOR.
crc16cc Use CRC16_CCITT — 16 bit CRC16 using CRC16-CCITT polynomial.
crc32MSB Use CRC32_UPPER — MSB 16 bits of computed CRC32.
crc32LSB Use CRC32_LOWER — LSB 16 bits of computed CRC32.
stack-unit unit
number
Enter the keywords stack-unit then the stack unit number. The range is from 0
to 7.
port-set port-
pipe
Enter the keywords port-set then the port pipe number. The range is from 0 to
5.
Defaults crc16 algorithm
438 Equal Cost Multi-Path (ECMP)