Addendum

condition occurs owing to hardware limitations in the S6000 platform, in which the RTAG7 hash
selection bitmap overlay bits 2 and 3 need to be enabled for the Flex Hash algorithm and to be
disabled for IP and Layer 2 trace flow feature. IP and Layer 2 trace flow feature is useful in identifying
the egress interface that the packet uses to pass through or traverse for port-channel and ECMP links.
If these overlay bits are enabled, the hashing algorithm calculation contains the source module and
source port ID, which causes an incorrect hash value to be computed for the flow packets.
load-balance ingress-port enable
Enable the Flex hash functionality. This utility is supported on the S6000 platform.
Syntax
load-balance ingress-port enable
To disable the Flex hash capability, use the no version of this command.
Default None
Command
Modes
CONFIGURATION mode
Command
History
Version 9.3.0.0 Introduced on the S6000 platform
Usage
Information
Flex hash uses the RTAG7 bins 2 and 3 (overlay bins). These bins must be enabled
for Flex hash to be configured. These bins contain the source module and source
port information. These bins are disabled by default in releases of Dell Networking
OS earlier than Release 9.3.0.0. The default behavior of disabling of these bins
occurs because of incorrect egress port information that would otherwise be
displayed in the output of the diagnostic show command of show ip flow.
As a result, when load balancing of RRoCE packets using Flex hash is enabled, the
show ip flow command is not functional. Similarly, when show ip flow
command operates (ingress port based load balancing is disabled) the hashing of
RRoCE packets is not operational.
Flex hash APIs do not mask out unwanted byte values after extraction of the data
from the Layer 4 headers for the offset value.
Example
S4810-YU-MR-FTOS(conf)#load-balance ingress-port enable
load-balance flexhash
Specify the parameters for the Flex Hash mechanism, such as whether IPv4 or IPv6 packets must be
subject to Flex Hash functionality, a unique protocol number, the offset of hash fields from the start of
the L4 header to be used for hash calculation, and a meaningful description to associate the protocol
number with the name. This utility is supported on the S6000 platform.
Syntax
load-balance flexhash ipv4/ipv6 ip-proto <protocol number>
<description string> offset1 <offset1 value> [offset2 <offset2
value>]
To disable the Flex hash settings, use the no load-balance flexhash ipv4/
ipv6 ip-proto protocol number command.
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Flex Hash and Optimized Boot-Up