Posted by: Anonymous
on May 07, 2008 02:21 PM
Regarding bonding in a load balancing configuration, last time I checked (few years ago) it was necessary that the switch that you connected to was also configured to bond the two ports used for bonding (this is called EtherChannel in Cisco parlance, and Linux is compatible with it).
If you don't, the switch is going to see the same MAC address coming from two different ports, and either a) won't know what to do and disable (probably) one of the ports; or b) replicate all traffic on both ports, which will double your traffic and thus negate the benefits of bonding.
And yes, the bond needs to have one and only one MAC, to maintain the mapping one IP -> one mac (the complimentary is not necessarily true, but it does not matter in this case). The packets going out of a bond won't get the MAC of the interface they get out through, but will get the (fictional) bond MAC.