Addendum

Parameters
ipv4 Denotes whether Flex Hash needs to be enabled for IPv4
packets.
ipv6 Denotes whether Flex Hash needs to be enabled for IPv6
packets.
protocol
number
Represents the Outer IPv4 protocol field in case of IPv4
packets, and the Outer IPv6 next header field in case of IPv6
packets.
The ipv4/ipv6 keyword and the IP protocol value are used
as keys to identify if a duplicate flex hash configuration is
already present. Duplicate flex hash configuration is not
possible. To change an existing flex hash configuration, you
must delete the existing flex hash attribute and configure the
flex attribute afresh.
description
string
A description string is followed by the protocol number to
enable you to associate the protocol number with the
protocol name in an easily-identifiable way. For example, for
a protocol number of 254, you can specify the description as
RRoCE.
offset1 value Specify the byte offset from the start of the L4 header from
which the 2-byte data is extracted and be used in hash
computation. You must enter the offset as an even number.
The offset range is 0 – 30 bytes from start of L4 header.
offset2 value (Optional) Specify the additional 2 bytes that must be
extracted from the start of the L4 header to be used for hash
computation. You must enter the offset as an even number.
The offset range is 0 – 30 bytes from start of L4 header.
Default None
Command
Modes
CONFIGURATION mode
Command
History
Version 9.3.0.0 Introduced on the S6000 platform
Usage
Information
With the introduction of various overlay technologies such as network virtualization
using generic routing encapsulation (NVGRE) segments and Routable Remote
Direct Memory Access (RRDMA) over Converged Ethernet (RRoCE), information
related to a traffic flow is contained in the L4 header. The fields in the L2 and L3
headers are not sufficient to distinguish the flows. Therefore, the fields in the L4
header are processed when hashing is performed for packets over LAG and ECMP
links. The Flex Hash functionality enables you to configure a packet search key and
matches packets based on the search key. When a packet matches the search key,
two 16-bit hash fields are extracted from the start of the L4 header and provided as
inputs (bins 2 and 3) for RTAG7 hash computation. You must specify the offset of
hash fields from the start of the L4 header, which contains a flow identification
field.
Flex Hash and Optimized Boot-Up
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