Linux NIC bonding

I'm building a cluster using Oracle Clusterware and have configured redundant pairs of NICs on the Linux servers using the Linux bonding module (active-passive). I know how to configure the Linux end of things and that's working fine. However, the switches used by this customer (they're Dell branded--not sure who really makes the guts) have been getting "confused" by bonding and our simple ping tests lose about 50% of the packets when we plug the redundant pairs into the two separate (trunked) switches.

This is only peripherally related to Oracle--it's really a networking and server config issue, but I'm hoping that someone with more networking background than I have can explain what switch configuration will enable this to work properly. The customer has stated that this will never work (though I have done it before at other sites and it worked fine). The customer has stated that the Linux configuration must be two active NICs  with a virtual IP and virtual MAC. I imagine that will work, but I'm not familiar with that configuration and I don't think Linux has native support for it, so it'd probably be a Broadcom or Intel software package. It's questionable how Oracle would view that from a support perspective (if they care at all).

So, the question: Is there some "magical" switch setting that would possibly be missing in a fairly "default" configuration that might enable this to work properly? I figure it's a long shot asking a networking question on the Oracle list, but thanks for any pointers.

Dan

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