Yes, that works for me :-)

With regards
Kings

On Sat, Aug 13, 2011 at 3:10 AM, Mark Senteza <[email protected]>wrote:

> Thanks Kings,
>
> so when asked to match BPDUs, its better to specify both "lsap 0xAAAA" and
> "lsap 0x4242" ?
>
> Mark
>
>
> On Thu, Aug 11, 2011 at 10:46 PM, Kingsley Charles <
> [email protected]> wrote:
>
>> IEEE STP BPDUs (uses 803.2 with 802.2) are sent vlan 1 on trunk ports
>> (802.1q) irrespective of whether it is the native or non-native vlan.
>> It can be matched using "permit any any lsap 0x4242 0x0".
>>
>> PVST+ BPDUs (Uses 803.2 with SNAP) are sent on other vlans excluding vlan
>> 1 on trunk port (802.1q). It can be match using "permit any any lsap 0xAAAA
>> 0x0" or "permit any any 0x010B 0x0".
>>
>>
>> mac access-list extended BPDU
>> permit any any lsap 0xAAAA
>>
>> permit any any lsap 0x4242
>>
>> or
>>
>>
>> mac access-list extended BPDU
>> permit any any 0x010B 0x0
>>
>> permit any any lsap 0x4242
>>
>>
>> I prefer first one as 0xAAAA also permits cdp, vtp etc along with PVST+
>> BPDUs.
>>
>>
>> With regards
>> Kings
>>
>> On Fri, Aug 12, 2011 at 3:26 AM, Mark Senteza <[email protected]>wrote:
>>
>>> Hey
>>>
>>> What values do you match when asked to filter STP BPDUs, for both 802.1q
>>> and ISL trunks ?
>>>
>>> I've read that IEEE STP BPDUs use 802.2 LLC encapsulation with SSAP/DSSP
>>> values of 0x42 or LSAP value of 0x4242. The document further states that you
>>> can also see STP packets sent across ISL trunks using the same LSAP value of
>>> 0x42.
>>>
>>> PVST+ BPDUs use 802.2 SNAP encapsulation, with LSAP=0xAAAA. All
>>> SNAP-encapsulated packets can be matched using an LSAP value of 0xAAAA.
>>>
>>> So, my question is, in order to match STP BPDUs for both 802.1q and ISL
>>> trunks, would I have to do the following:
>>>
>>>    mac access-list extended BPDU
>>>     permit any any 0xAAAA 0x0
>>>     permit any any lsap 0x4242
>>>
>>>
>>>
>>> _______________________________________________
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>>
>>
>
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