[c-nsp] General switching question regarding load balancing host

[Jay Nakamura]

Some hosts/OS can do load balancing between NICs.  If a host has two
NICs connected to two switches,(the two switches are connected
together) and load balancing between them, switch will see the same
source MAC from two ports.  How does a switch decide which ports to
put in the forwarding table?  Would it switch back and forth every
time there is a packet?  Is there any negative effect on the switch
when that happens?  Is this platform dependent?

Sorry for the generalized question.