Concept Guide

ip address ip-address mask [secondary]
– ip-address mask: enter an address in dotted-decimal format (A.B.C.D). The mask must be in slash format (/24).
– secondary: the IP address is the interface’s backup IP address. You can congure up to eight secondary IP addresses.
Deleting or Disabling a Port Channel
To delete or disable a port channel, use the following commands.
• Delete a port channel.
CONFIGURATION mode
no interface portchannel channel-number
• Disable a port channel.
shutdown
When you disable a port channel, all interfaces within the port channel are operationally down also.
Load Balancing Through Port Channels
Dell EMC Networking OS uses hash algorithms for distributing trac evenly over channel members in a port channel (LAG).
The hash algorithm distributes trac among Equal Cost Multi-path (ECMP) paths and LAG members. The distribution is based on a ow,
except for packet-based hashing. A ow is identied by the hash and is assigned to one link. In packet-based hashing, a single ow can be
distributed on the LAG and uses one link.
Packet based hashing is used to load balance trac across a port-channel based on the IP Identier eld within the packet. Load balancing
uses source and destination packet information to get the greatest advantage of resources by distributing trac over multiple paths when
transferring data to a destination.
Dell EMC Networking OS allows you to modify the hashing algorithms used for ows 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.
The nh-ecmp option allows you to change the hash value for recursive ECMP routes independently of non-recursive ECMP routes. This
option provides for better trac distribution over available equal cost links that involve a recursive next hop lookup.
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 {algorithm-number | {ecmp {crc16 | crc16cc | crc32MSB | crc32LSB | crc-upper |
dest-ip | lsb | xor1 | xor2 | xor4 | xor8 | xor16} [number] hg {crc16 | crc16cc | crc32MSB |
crc32LSB | xor1 | xor2 | xor4 | xor8 | xor16} stack-unit stack-unit-number | port-set port-
pipe | hg-seed seed-value stack-unit | lag {checksum | crc | xor} [number] nh-ecmp {checksum |
crc | xor}[number] stack—unit number ip-sa-mask value ip-da-mask value | seed seed-value }
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Interfaces