I think that there's a little gap there....

ARP is definitely necessary, but with your lsap 0xaaaa you are permitting
ANY Ethernet_SNAP frames to go across.  The fact that Cisco use SNAP for
PVST+ is just one piece of the puzzle there.  (normal STP is 0x4242)

You need to look for a destination MAC address of 01-00-0c-cc-cc-cd in
addition to the SNAP frame.

Where are those things?  Good luck with that.  :)  AFAIK it's not a
well-documented feature.  You can find the 0x4242 in the IBM Bridging
documentation someplace, but the PVST+ information MIGHT be in the switch's
spanning tree section, but I don't recall seeing it.  I don't recall looking
either though! 

HTH,

Scott

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Louis S
Sent: Tuesday, June 03, 2008 9:07 PM
To: osl
Subject: [OSL | CCIE_RS] VACL question / remembering hex codes necessary?

So something as simple as only allowing IOP traffic to transit a vlan...

Now if we have spanning-tree and arp running on here we would have to
remmber to permit those in the VACL as well.

If their a doccd ref or something may help out with this configuration or
are we just supposed to memorize it ?

maybe we could just apply what we know and then debug the vacl?

ie)

ip access-list extended IPONLY
PERMIT IP ANY ANY

mac access-list extended IP_ARP
permit any any 0x806 0x0

mac access-list extended PVSTPLUS_STP
permit any any lsap 0xaaaa 0x0

vlan access-map IPONLY 10
action forward
match ip address IPONLY

vlan access-map IPONLY 20
action forward
match mac address IP_ARP

vlan access-map IPONLY 30
action forward
match mac address PVSTPLUS_STP

vlan access=-map IPONLY 40
action drop

vlan filter IPONLY vlan-list 100


      

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