| The multicast forwarding rate is handled differently in the case of
the GIGAswitch versus bridge modules. The bridges use the MIB variable
ebrRateLimit - This is the maximum number of rate-limited frames
per second that the bridge will forward.
This can be set on a per address or protocol basis from what I understand.
The GIGAswitch uses something different. They are two MIB variables
floodUnknownUnicastRate - The maximum bytes per second bandwidth of
packets multicast because the destination
address was not yet learned by the bridge.
floodMulticastRate - The maximum bytes per second bandwidth of
packets multicast because the destination
address is a multicast address.
It is probably the second you are interested in. I'm not sure why GIGAswitch
implements it this way but note this is limited as bytes per second versus
frames (or packets) per second in the bridge case. There seems to be no
distinction of traffic based on protocol or address in the GIGAswitch case.
So if you're getting broadcast storms under one protocol you possibly limit
other protocol's multicast that was behaving correctly.
HUBwatch does not support the two GIGAswitch MIB variables right
now. If you think if may be useful, let us know and we can evaluate how
much work it may be.
John
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