Users Guide
Dell Networking OS allows you to modify the hashing algorithms used for flows and for fragments. The load-balance and hash-algorithm
commands are available for modifying the distribution algorithms.
Changing the Hash Algorithm
The load-balance command selects the hash criteria applied to port channels.
If you do not obtain even distribution with the load-balance command, you can use the hash-algorithm command to select the
hash scheme for LAG, ECMP and NH-ECMP. You can rotate or shift the 12–bit Lag Hash until the desired hash is achieved.
To change to another algorithm, use the second command.
• Change the default (0) to another algorithm and apply it to ECMP, LAG hashing, or a particular line card.
CONFIGURATION mode
hash-algorithm {ecmp {crc16 | crc16cc | crc32MSB | crc32LSB | crc-upper | dest-ip | flow-
based-hashing {crc16|crc16cc|crc32MSB|crc32LSB|xor1|xor2|xor4|xor8|xor16}|lsb | xor1 | xor2 |
xor4 | xor8 | xor16}[[hg {crc16 | crc16cc | crc32MSB | crc32LSB | xor1 | xor2 | xor4 | xor8 |
xor16}]| [lag {crc16 | crc16cc | crc32MSB | crc32LSB | xor1 | xor2 | xor4 | xor8 | xor16 }]
[stack-unit|linecard number | port-set number | [hg—seed seed-value | seedseed-value
For more information about algorithm choices, refer to the command details in the IP Routing chapter of the Dell Networking OS
Command Reference Guide.
• Change to another algorithm.
CONFIGURATION mode
hash-algorithm [ecmp{crc16|crc16cc|crc32LSB|crc32MSB|crc-upper|dest-ip|lsb|xor1|xor2|xor4|
xor8|xor16}]
The hash-algorithm command is specific to ECMP group. The default ECMP hash configuration is crc-lower. This command takes
the lower 32 bits of the hash key to compute the egress port. Other options for ECMP hash-algorithms are:
Bulk Configuration
Bulk configuration allows you to determine if interfaces are present for physical interfaces or configured for logical interfaces.
Interface Range
An interface range is a set of interfaces to which other commands may be applied and may be created if there is at least one valid
interface within the range.
Bulk configuration excludes from configuration any non-existing interfaces from an interface range. A default VLAN may be configured
only if the interface range being configured consists of only VLAN ports.
The interface range command allows you to create an interface range allowing other commands to be applied to that range of
interfaces.
The interface range prompt offers the interface (with slot and port information) for valid interfaces. The maximum size of an interface
range prompt is 32. If the prompt size exceeds this maximum, it displays (...) at the end of the output.
NOTE: Non-existing interfaces are excluded from the interface range prompt.
NOTE: When creating an interface range, interfaces appear in the order they were entered and are not sorted.
The show range command is available under Interface Range mode. This command allows you to display all interfaces that have been
validated under the interface range context.
The show configuration command is also available under Interface Range mode. This command allows you to display the running
configuration only for interfaces that are part of interface range.
You can avoid specifying spaces between the range of interfaces, separated by commas, that you configure by using the interface
range command. For example, if you enter a list of interface ranges, such as interface range fo 2/50-2/53,te 1/1, this
configuration is considered valid. The comma-separated list is not required to be separated by spaces in between the ranges. You can
associate multicast MAC or hardware addresses to an interface range and VLANs by using the mac-address-table static
multicast-mac-address vlan vlan-id output-range interface command.
Interfaces
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