Traffic that flows across a port-channel is not forwarded out member links in a round robin basis. A hash is calculated and packets are consistently forwarded across a link based on that calculated hash.
The load balancing hash is a system wide configuration that uses a global command: port-channel load-balance X where X is the hash from the following selections:
| Hash algorithm | Description |
| dst-ip | Balances based on destination IP and MAC address only |
| dst-mac | Balances based on destination MAC address only |
| dst-mixed-ip-port | Balances based on destination IP and MAC address and TCP/UDP port |
| dst-port | Balances based on destination port only |
| src-dst-ip | Balances based on source IP and destination IP address and MAC addresses |
| src-dst-ip-only | Balances based on source IP and destination IP address without MAC address information |
| src-dst-mac | Balances based on source and destination MAC addresses |
| src-dst-mixed-ip-port | Balances based on source and destination IP addresses along with source and destination TCP/UDP ports |
| src-dst-port | Balances based on source and destination TCP/UDP ports only |
| src-ip | Balances based on source IP address only |
| src-mac | Balances based on source MAC address only |
| src-mixed-ip-port | Balances based on source IP address and TCP/UDP port |
| src-port | Balances on source port only |
Changing the hash may be beneficial to systems that see very high utilisation on one or two member links in a port channel.
Hashing is a binary function; it is important to note that load balancing works best in situations where the number of links are in powers of two. A two or four link etherchannel will load balance better than a three or five link etherchannel.
The command show etherchannel load-balance will display how the switch will load balance its network traffic.
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