Dell S5148F-ON OS10 Enterprise Edition User Guide Release 10.3.2E-R2 - Page 241

Equal cost multi-path, Load balancing, ECMP commands

Page 241 highlights

Equal cost multi-path ECMP is a routing technique where next-hop packet forwarding to a single destination occurs over multiple best paths. OS10 uses a hashing algorithm to determine the next-hop when you enable ECMP. The hashing algorithm makes hashing decisions based on values in various packet fields as well as some internal values. • Configure the hash algorithm in CONFIGURATION mode. hash-algorithm ecmp crc Change hash algorithm OS10(config)# hash-algorithm ecmp crc Load balancing RTAG7 is a hashing algorithm that load balances traffic within a trunk group in a controlled manner. To effectively increase the bandwidth of ECMP routes, traffic is balanced across member links. The balancing is performed by using the RTAG7 hashing, which is designed to have the member links used effectively as the traffic profile gets more diverse. The RTAG7 hash scheme generates a hash that consists of two parts: • The first part is primarily generated from packet headers to identify micro-flows in traffic. By default, all listed parameters are enabled for load balancing except the ingress port. OS10# show load-balance Load-Balancing Configuration For LAG and ECMP: IPV4 Load Balancing : Enabled IPV6 Load Balancing : Enabled MAC Load Balancing : Enabled TCP-UDP Load Balancing : Enabled Ingress Port Load Balancing : Disabled IPV4 FIELDS : source-ip destination-ip protocol vlan-id l4-destination-port l4-source-port IPV6 FIELDS : source-ip destination-ip protocol vlan-id l4-destination-port l4-source-port MAC FIELDS : source-mac destination-mac ethertype vlan-id TCP-UDP FIELDS: l4-destination-port l4-source-port • The second part comes from static physical configuration such as ingress and egress port numbers. You can change the hash field to generate load balancing based on any parameters using the load-balance command. ECMP commands hash-algorithm Changes the hash algorithm that distributes traffic flows across ECMP paths and the LAG. Syntax Parameters hash-algorithm {ecmp | lag} crc • ecmp - Enables ECMP hash configuration. • lag - Enables LAG hash configuration for L2 only. • crc - Enables CRC polynomial for hash computation. Layer 3 241

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Equal cost multi-path
ECMP is a routing technique where next-hop packet forwarding to a single destination occurs over multiple best paths. OS10 uses a
hashing algorithm to determine the next-hop when you enable ECMP. The hashing algorithm makes hashing decisions based on values in
various packet
fields
as well as some internal values.
Configure
the hash algorithm in CONFIGURATION mode.
hash-algorithm ecmp crc
Change hash algorithm
OS10(config)# hash-algorithm ecmp crc
Load balancing
RTAG7 is a hashing algorithm that load balances
traffic
within a trunk group in a controlled manner. To
effectively
increase the bandwidth of
ECMP routes,
traffic
is balanced across member links. The balancing is performed by using the RTAG7 hashing, which is designed to have
the member links used
effectively
as the
traffic
profile
gets more diverse.
The RTAG7 hash scheme generates a hash that consists of two parts:
The
first
part is primarily generated from packet headers to identify
micro-flows
in
traffic.
By default, all listed parameters are enabled
for load balancing except the ingress port.
OS10# show load-balance
Load-Balancing Configuration For LAG and ECMP:
----------------------------------------------
IPV4 Load Balancing
: Enabled
IPV6 Load Balancing
: Enabled
MAC Load Balancing
: Enabled
TCP-UDP Load Balancing
: Enabled
Ingress Port Load Balancing : Disabled
IPV4 FIELDS
: source-ip destination-ip protocol vlan-id l4-destination-port l4-source-port
IPV6 FIELDS
: source-ip destination-ip protocol vlan-id l4-destination-port l4-source-port
MAC FIELDS
: source-mac destination-mac
ethertype
vlan-id
TCP-UDP FIELDS: l4-destination-port
l4-source-port
The second part comes from static physical
configuration
such as ingress and egress port numbers.
You can change the hash
field
to generate load balancing based on any parameters using the
load-balance
command.
ECMP commands
hash-algorithm
Changes the hash algorithm that distributes
traffic
flows
across ECMP paths and the LAG.
Syntax
hash-algorithm {ecmp | lag} crc
Parameters
ecmp
— Enables ECMP hash
configuration.
lag
— Enables LAG hash
configuration
for L2 only.
crc
— Enables CRC polynomial for hash computation.
Layer 3
241