You have a Cisco MDS switch that uses port channel. You must ensure that frames between the source and the destination follow the same links for a specific flow. Subsequent flows can use a different link, which load-balancing method do you use?
A. Source-destination-ip
B. Source-destioation-port
C. Flow
D. Source id-destination id-oxid
After some further research, it turns out the answer “Flow” is the right answer.
This is because this relates to an MDS9000 on FC, not a regular Ethernet switch (for which my previous post would have been OK).
But for the MDS9000, the right info can be found here:
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/mds9000/sw/5_0/configuration/guides/int/nxos/cli_interfaces/pc.html
And the answer is “Flow”….Live &Learn.
No such answer as “Flow”.
The options for port-channel load balancing are:
destination-ip —Loads distribution on the destination IP address.
destination-mac —Loads distribution on the destination MAC address.
destination-port —Loads distribution on the destination port.
source-destination-ip —Loads distribution on the source and destination IP address.
source-destination-mac —Loads distribution on the source and destination MAC address.
source-destination-port —Loads distribution on the source and destination port.
source-ip —Loads distribution on the source IP address.
source-mac —Loads distribution on the source MAC address.
source-port —Loads distribution on the source port.
See details below:
https://www.cisco.com/c/m/en_us/techdoc/dc/reference/cli/nxos/commands/l2/port-channel-load-balance-ethernet.html
As the question refers to “flow” and it states subsequent “flows” between source and destination can change (so same IP remain for both), it sounds like the right answer is B – load balancing based on port.
As an application (a “flow”) has finished its send/receive, a new connection from another one would use a different port and it would be balanced on a different link.