I have a question regarding etherchannel load balancing. I've got a4507R switch connected to a 3560 switch by means of two content filters which are acting as transparent bridges. The two ports on each side that the content filters are connected to are set up as access ports and are in an etherchannel. The load balancing method on each switch is set to src-dst-ip. I was under the impression that each pair of source and destination ip address would select exactly one content filter no matter which direction.
I've been told that this can be 'unpredictable' and may cause assymetric flows. The algorithm seems fairly straightforward to me. I don't see where the unpredictability can come in. Can someone explain to me what I'm missing?