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5308xl and STP

Konstantin_5
Occasional Contributor

5308xl and STP

How would I block STP BPDU ?
I'm trying:
>filter multicast 0180c2-000000 drop c2
but answer:
Unable to add filter.
why ?
(stp disabled)
4 REPLIES
Marcus_20
Frequent Advisor

Re: 5308xl and STP

When STP is disabled the switch does not propagete STP BPDUs... Thus a Layer 2 interface in the disabled state does not participate in frame forwarding or in the spanning tree. An interface in the disabled state is nonoperational.
/marcus
Dmitry G. Spitsyn
Trusted Contributor

Re: 5308xl and STP

RFC 1700 Assigned Numbers tells us that, for IP multicast packets, the upper 24 bits
of the Ethernet address are always 0x01005E. HP Procurve switches
look for 0x01005E at the beginning of the destination MAC address in order to
identify IP multicast packets that it should consider for pruning.

BR,
Dmitry.
Konstantin_5
Occasional Contributor

Re: 5308xl and STP

01-80-C2-00-00-00-Spanning tree (for bridges)
01-80-C2-00-00-01 through 01-80-c2-00-00-0f -802.1 alternate Spanning multicast
(RFC-1700)
01-00-5E-00-00-00 through 01-00-5E-7F-FF-FF -DoD Internet Multicast (RFC-1112)
Dmitry G. Spitsyn
Trusted Contributor

Re: 5308xl and STP

Absolutely !!!
It means that the multicast addresses mentioned by you are not considered for pruning by multicast filtering!

BR,
Dmitry