Interesting. In the case that it's an OR match only, this solution wouldn't
actually work. The reason that I grouped the mac and IP match statments in
the same access-map sequence is because I assumed that it would default to
'AND', OR being if you dropped them in different sequences.

Bummer.

-Buck

On Thu, Apr 15, 2010 at 2:30 AM, Kingsley Charles <
[email protected]> wrote:

> Hi Brandon
>
> I just checked and it seems the vlan access-map is making "OR" logic
> between the matching criterias. With following config, either it matches
> mac acl "king" or IP acl "123".
>
> vlan access-map king 10
>  action drop
>  match mac address king
>  match ip address 123
>
> While the route-maps uses "AND" logic between the criteria.
>
>
> With regards
> Kings
>
> On Thu, Apr 15, 2010 at 12:27 PM, Brandon Carroll 
> <[email protected]>wrote:
>
>>  Kings,
>>
>> It's a logical and like a route-map.
>>
>> Regards,
>>
>> Brandon Carroll - CCIE #23837
>> Senior Technical Instructor - IPexpert
>> Mailto: <[email protected]>[email protected]
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>> On Apr 14, 2010, at 11:42 PM, Kingsley Charles <
>> [email protected]> wrote:
>>
>>   That should work. But the question was in general to prevent spoofing
>> without using DAI. We don't know the IP address and
>> MAC addresses that will flow across.
>>
>> One question, with vlan-access maps, if there are more than two match
>> criterias is it match-any or match-all?
>>
>> With regards
>> Kings
>>
>> On Thu, Apr 15, 2010 at 5:43 AM, bwalla < <[email protected]>
>> [email protected]> wrote:
>>
>>> This is actually a great question which I've seen come up as well. 
>>> Depending on the requirements, step 2 seems like it may be a little extreme.
>>>
>>>
>>>
>>> PLEASE correct me if you see something wrong with this, but wouldn't the 
>>> following be a working solution as well?
>>>
>>> Assuming we only want host 192.168.123.1 with a MAC of 001f.ca08.105c to 
>>> communicate on vlan 123...
>>>
>>> access-list 123 permit ip host 192.168.123.1 any
>>>
>>> mac access-list extended no_spoof
>>>  permit host 001f.ca08.105c any
>>>
>>>
>>>
>>>
>>> vlan access-map anti-spoof 10
>>>  action forward
>>>  match mac address no_spoof
>>>  match ip address 123
>>> vlan access-map anti-spoof 20
>>>  action drop
>>>
>>> vlan filter anti-spoof vlan-list 123
>>>
>>>
>>> On Mar 17, 2010, at 12:09 AM, Kingsley Charles wrote:
>>>
>>>
>>>
>>>
>>> >* Hi all
>>> *>*
>>> *>* I just came across this question.
>>> *>*
>>> *>* How do we prevent arp spoofing on switches without using DAI.
>>> *>*
>>> *>* My solution is as following:
>>>
>>>
>>>
>>> *>*
>>> *>* Solution 1
>>> *>* ========
>>> *>*
>>> *>* Configure "ip source" guard with port security. With this only arp 
>>> packets with valid source IP and MAC address will be forward across the
>>>
>>>
>>>
>>> *>* switch and hence, no one can spoof the IP address with another MAC 
>>> address.
>>> *>*
>>> *>*
>>> *>* Solution 2
>>> *>* ========
>>> *>*
>>> *>* Here I am dropping all the ARP traffic across vlan 3 where I am 
>>> suspecting spoofing attack.
>>>
>>>
>>>
>>> *>*
>>> *>* mac access-list extended arp
>>> *>*  permit any any 0x806 0x0
>>> *>*
>>> *>* vlan access-map arp 10
>>> *>*  action drop
>>> *>*  match mac address arp
>>>
>>>
>>>
>>> *>*
>>> *>* vlan access-map arp 10
>>> *>* action forward
>>> *>*
>>> *>* vlan filter arp vlan-list 3
>>> *>*
>>> *>*
>>> *>* Since the ARP is being dropped. The MAC addresses of the remote hosts 
>>> should be statically configured each hosts.
>>>
>>>
>>>
>>> *>* On the router, we can add the arp statically with the following command
>>> *>*
>>> *>* router(config)#arp 10.20.30.42 3.3.3 arpa
>>> *>*
>>> *>*
>>> *>*
>>> *>* Also the switch needs to know, where to forward the mac address.
>>>
>>>
>>>
>>> *>*
>>> *>* sw(config)#mac-address-table static 3.3.3 vlan 3 interface f1/0/2
>>> *>*
>>> *>*
>>> *>*
>>> *>*
>>> *>* If you have any other solutions, please do share it.
>>>
>>>
>>>
>>> *>*
>>> *>*
>>> *>*
>>> *>* With regards
>>> *>* Kings
>>> *>* _______________________________________________
>>> *>* For more information regarding industry leading CCIE Lab training, 
>>> please visit  <http://www.ipexpert.com/>www.ipexpert.com
>>>
>>>
>>>
>>> *
>>>
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training, please
>>> visit <http://www.ipexpert.com/>www.ipexpert.com
>>>
>>>
>>  _______________________________________________
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>> visit <http://www.ipexpert.com/>www.ipexpert.com
>>
>>
>
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