Yes, I heard that too and I think it's resolved in the latest images.

With regards
Kings

On Thu, Jun 9, 2011 at 3:21 PM, Bruno <[email protected]> wrote:

> Just 1 cent.
>
> "permit any any 0x10B 0x0" on 3550 does NOT work as expected. Maybe a bug
> or so.
> So, I will go always with 0xAAAA 0x0
>
>
> On Thu, Jun 9, 2011 at 1:38 AM, Kingsley Charles <
> [email protected]> wrote:
>
>> SNAP identifies the upper protocol using a 2 byte "Ethertype?" field which
>> is also referred as protocol identifier. Hence the following ACE will match
>> PVST+ BPDUs. I have confirmed it in my lab.
>>
>> permit any any 0x010B 0x0
>>
>> The above will allow only PVST+ BPDUs. The below will also allow VTP, CDP
>> which uses SNAP.
>>
>> permit any any lsap 0xAAAA 0x0
>>
>>
>> With regards
>> Kings
>>
>>
>> On Wed, Jun 8, 2011 at 8:17 PM, Antonio Soares <[email protected]>wrote:
>>
>>> I agree with all you said except matching the PVST+ BPDUs with:
>>>
>>>
>>>
>>> "permit any any 0x010B 0x0"
>>>
>>>
>>>
>>> The value there is an Ethertype.
>>>
>>>
>>>
>>> Switch(config-ext-macl)#permit any any ?
>>>
>>>   <0-65535>     An arbitrary EtherType in decimal, hex, or octal
>>>
>>>   aarp          EtherType: AppleTalk ARP
>>>
>>>   amber         EtherType: DEC-Amber
>>>
>>>   appletalk     EtherType: AppleTalk/EtherTalk
>>>
>>>   cos           CoS value
>>>
>>>   dec-spanning  EtherType: DEC-Spanning-Tree
>>>
>>>   decnet-iv     EtherType: DECnet Phase IV
>>>
>>>   diagnostic    EtherType: DEC-Diagnostic
>>>
>>>   dsm           EtherType: DEC-DSM
>>>
>>>   etype-6000    EtherType: 0x6000
>>>
>>>   etype-8042    EtherType: 0x8042
>>>
>>>   lat           EtherType: DEC-LAT
>>>
>>>   lavc-sca      EtherType: DEC-LAVC-SCA
>>>
>>>   lsap          LSAP value
>>>
>>>   mop-console   EtherType: DEC-MOP Remote Console
>>>
>>>   mop-dump      EtherType: DEC-MOP Dump
>>>
>>>   msdos         EtherType: DEC-MSDOS
>>>
>>>   mumps         EtherType: DEC-MUMPS
>>>
>>>   netbios       EtherType: DEC-NETBIOS
>>>
>>>   vines-echo    EtherType: VINES Echo
>>>
>>>   vines-ip      EtherType: VINES IP
>>>
>>>   xns-idp       EtherType: XNS IDP
>>>
>>>   <cr>
>>>
>>>
>>>
>>> Switch(config-ext-macl)#
>>>
>>>
>>>
>>> The 0x010B value is the LLC Protocol Identifier.
>>>
>>>
>>>
>>> So you need these two:
>>>
>>>
>>>
>>> PVST+
>>>
>>> permit any any lsap 0xAAAA 0x0
>>>
>>>
>>>
>>> STP
>>>
>>> permit any any lsap 0x4242 0x0
>>>
>>>
>>>
>>>
>>>
>>> Regards,
>>>
>>>
>>>
>>> Antonio Soares, CCIE #18473 (R&S/SP)
>>> [email protected]
>>>
>>> http://www.ccie18473.net
>>>
>>>
>>>
>>>
>>>
>>> *From:* Kingsley Charles [mailto:[email protected]]
>>> *Sent:* quarta-feira, 8 de Junho de 2011 12:19
>>>
>>> *To:* Antonio Soares
>>> *Cc:* Bruno; [email protected]
>>> *Subject:* Re: [OSL | CCIE_Security] Permitting STP BPDUs
>>>
>>>
>>>
>>> I do see PVST+ SSTP now :-)
>>>
>>> I will put my understanding.
>>>
>>>
>>>
>>> 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".
>>>
>>>
>>>
>>> On ISL IEEE STP BPDUs (uses 803.2 with 802.2) are tagged with ISL header
>>> and it can be matched with "permit any any lsap 0x4242 0x0".
>>>
>>>
>>>
>>>
>>>
>>> Please let me know, your thoughts.
>>>
>>>
>>>
>>> With regards
>>>
>>> Kings
>>>
>>>
>>>
>>> On Wed, Jun 8, 2011 at 4:09 PM, Kingsley Charles <
>>> [email protected]> wrote:
>>>
>>> I am using 802.1q not ISL.
>>>
>>> Can you let me know your thoughts on the following statements
>>>
>>>    - IEEE STP BPDU should be seen on vlan 1 configured as the native
>>>    vlan and access port only.
>>>    - PVST+ BPDU should be seen on vlans of trunk other than vlan 1.
>>>
>>>
>>>
>>>
>>> With regards
>>> Kings
>>>
>>>
>>>
>>> On Wed, Jun 8, 2011 at 3:50 PM, Antonio Soares <[email protected]>
>>> wrote:
>>>
>>> By default, the switches will negotiate an ISL trunk and in this type of
>>> trunk you only have STP BPDUs. Change it to Dot1Q and you will see the
>>> difference.
>>>
>>>
>>>
>>> The ACLs should be:
>>>
>>>
>>>
>>> permit any any lsap 0xAAAA 0x0
>>>
>>> permit any any lsap 0x4242 0x0
>>>
>>>
>>>
>>>
>>>
>>> Regards,
>>>
>>>
>>>
>>> Antonio Soares, CCIE #18473 (R&S/SP)
>>> [email protected]
>>>
>>> http://www.ccie18473.net
>>>
>>>
>>>
>>>
>>>
>>> *From:* Kingsley Charles [mailto:[email protected]]
>>> *Sent:* quarta-feira, 8 de Junho de 2011 11:02
>>> *To:* Antonio Soares
>>> *Cc:* Bruno; [email protected]
>>>
>>>
>>> *Subject:* Re: [OSL | CCIE_Security] Permitting STP BPDUs
>>>
>>>
>>>
>>> Great, that's a good a debug command for this topic.
>>>
>>> Ok when would we see liinktype of *linktype SSTP **and **inktype
>>> IEEE_SPANNING* is my next question.
>>>
>>>
>>> On a trunk port of a Cisco switch that connects to another Cisco switch,
>>> I see only IEEE STP BPDUs.
>>>
>>>
>>> When I use mac ACL as an access-group on switch l2 ports or with vlan
>>> access-groups, is it safe to always add the following:
>>>
>>> permit any any 0xAAAA 0x0
>>> permit any any lsap 0x4242 0x0
>>>
>>>
>>>
>>>
>>> With regards
>>> Kings
>>>
>>> On Tue, Jun 7, 2011 at 11:48 PM, Antonio Soares <[email protected]>
>>> wrote:
>>>
>>> If you are in the lab and you don’t remember these things, just enable
>>> “debug spanning-tree bpdu receive” and you will see (example with dot1q
>>> trunk, 3 vlans):
>>>
>>>
>>>
>>> *Mar 11 04:02:43.731: STP: *VLAN0001* rx BPDU: config protocol = ieee,
>>> packet from FastEthernet0/13  , *linktype IEEE_SPANNING* , enctype 2,
>>> encsize 17
>>>
>>> *Mar 11 04:02:43.731: STP: enc 01 80 C2 00 00 00 00 09 E8 CB 62 8D 00 26
>>> *42 42* 03
>>>
>>> *Mar 11 04:02:43.731: STP: Data
>>> 000000000080010009E8CB62800000000080010009E8CB6280800D0000140002000F00
>>>
>>> *Mar 11 04:02:43.735: STP: VLAN0001 Fa0/13:0000 00 00 00 80010009E8CB6280
>>> 00000000 80010009E8CB6280 800D 0000 1400 0200 0F00
>>>
>>> *Mar 11 04:02:43.735: STP(1) port Fa0/13 supersedes 0
>>>
>>>
>>>
>>> *Mar 11 04:02:45.435: STP: *VLAN0010* rx BPDU: config protocol = ieee,
>>> packet from FastEthernet0/13  , *linktype SSTP* , enctype 3, encsize 22
>>>
>>> *Mar 11 04:02:45.435: STP: enc 01 00 0C CC CC CD 00 09 E8 CB 62 8D 00 32
>>> *AA AA* 03 00 00 0C 01 0B
>>>
>>> *Mar 11 04:02:45.435: STP: Data
>>> 0000000000800A0009E8CB628000000000800A0009E8CB6280800D0000140002000F00
>>>
>>> *Mar 11 04:02:45.439: STP: VLAN0010 Fa0/13:0000 00 00 00 800A0009E8CB6280
>>> 00000000 800A0009E8CB6280 800D 0000 1400 0200 0F00
>>>
>>> *Mar 11 04:02:45.439: STP(10) port Fa0/13 supersedes 0
>>>
>>>
>>>
>>> *Mar 11 04:02:45.439: STP: *VLAN0020* rx BPDU: config protocol = ieee,
>>> packet from FastEthernet0/13  , *linktype SSTP* , enctype 3, encsize 22
>>>
>>> *Mar 11 04:02:45.439: STP: enc 01 00 0C CC CC CD 00 09 E8 CB 62 8D 00 32
>>> *AA AA* 03 00 00 0C 01 0B
>>>
>>> *Mar 11 04:02:45.439: STP: Data
>>> 000000000080140009E8CB62800000000080140009E8CB6280800D0000140002000F00
>>>
>>> *Mar 11 04:02:45.443: STP: VLAN0020 Fa0/13:0000 00 00 00 80140009E8CB6280
>>> 00000000 80140009E8CB6280 800D 0000 1400 0200 0F00
>>>
>>> *Mar 11 04:02:45.443: STP(20) port Fa0/13 supersedes 0
>>>
>>>
>>>
>>> STP-SNAP 0x4242 (lsap 0x4242 0x000)
>>>
>>> PVST+-SNAP 0xAAAA (lsap 0xAAAA 0x000)
>>>
>>>
>>>
>>>
>>>
>>> Regards,
>>>
>>>
>>>
>>> Antonio Soares, CCIE #18473 (R&S/SP)
>>> [email protected]
>>>
>>> http://www.ccie18473.net
>>>
>>>
>>>
>>>
>>>
>>> *From:* [email protected] [mailto:
>>> [email protected]] *On Behalf Of *Kingsley
>>> Charles
>>> *Sent:* terça-feira, 7 de Junho de 2011 17:22
>>> *To:* Bruno
>>> *Cc:* [email protected]
>>> *Subject:* Re: [OSL | CCIE_Security] Permitting STP BPDUs
>>>
>>>
>>>
>>> Does STP and PVST use EtherType? They use SNAP isn't it?
>>>
>>>
>>> With regards
>>> Kings
>>>
>>> On Tue, Jun 7, 2011 at 7:40 PM, Bruno <[email protected]> wrote:
>>>
>>> Hey King,
>>>
>>> STP and PVST should be matched on lsa type 0xaaaa I am not mistaken
>>> Ethertype should be 0x10b I think.
>>>
>>> On Tue, Jun 7, 2011 at 8:57 AM, Kingsley Charles <
>>> [email protected]> wrote:
>>>
>>>  Hi all
>>>
>>> I am using VACLs to block ARP in vlan X using the following command. This
>>> is going to block all non-ip traffic including the STP BPDUs. What is needed
>>> to permit the STP BPDUs to prevent looping?
>>>
>>> mac access-list extended king
>>> permit any any 0x0806
>>>
>>> vlan access-map king
>>> match mac address
>>> action drop
>>>
>>> vlan filter king vlan-list 123
>>>
>>>
>>>
>>>
>>> With regards
>>> Kings
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training, please
>>> visit www.ipexpert.com
>>>
>>> Are you a CCNP or CCIE and looking for a job? Check out
>>> www.PlatinumPlacement.com
>>>
>>>
>>>
>>>
>>> --
>>> Bruno Fagioli (by Jaunty Jackalope)
>>> Cisco Security Professional
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>
>
> --
> Bruno Fagioli (by Jaunty Jackalope)
> Cisco Security Professional
>
_______________________________________________
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