in the words of homer simpson - doh

good lesson, how could i miss it was in the dsg!

cheers all the same


On 28 August 2012 15:48, Andy Sajous <[email protected]> wrote:

> I think your missing a part on you MAC access-list.  Looks like you
> specified the ether type, but spanning tree is still failing because you're
> missing the LLC SNAP encapsulation (lsap).
>
> mac access-list extended FilterMe
> permit any any 0x0806 0x0000
> permit any any *lsap* 0xAAAA 0x0000
>
>
>
>
>
>
> On Tue, Aug 28, 2012 at 9:28 AM, Tony Singh <[email protected]> wrote:
>
> > Hi Experts
> >
> >
> > Please forgive rather long winded email but need direction here.....
> >
> >
> > *topology*
> > R1 f0/0 > f0/1 CAT 1 (vlan 12)
> > R2 f0/0 > f0/2 CAT 1 (vlan 12)
> >
> > *issue*
> > 01:50:21: %SW_MATM-4-MACFLAP_NOTIF: Host 001c.f691.a0f8 in vlan 12 is
> > flapping between port Po13 and port Po12
> > 01:50:21: %SW_MATM-4-MACFLAP_NOTIF: Host 001c.58a7.d388 in vlan 12 is
> > flapping between port Po14 and port Po12
> >
> > these flapps continue across all ether channels....
> >
> >
> > *R1#show ip arp *
> > Internet  150.100.12.1            -   001c.58a7.d388  ARPA
> > FastEthernet0/0
> > Internet  150.100.12.2            0   Incomplete      ARPA
> >
> > *R2#show ip arp*
> > Protocol  Address          Age (min)  Hardware Addr   Type   Interface
> > Internet  150.100.12.1            0   001c.58a7.d388  ARPA
> > FastEthernet0/0
> > Internet  150.100.12.2            -   001c.f691.a0f8  ARPA
> > FastEthernet0/0
> >
> > one end of either router's arp is always incomplete
> >
> > checked all ends, encaps is arpa with full-duplex 100mb/s
> >
> > *CAT1*
> > access-list 100 permit icmp any any
> > access-list 100 permit ospf any any
> >
> > mac access-list extended MAC
> > *permit mac any any 0x0806 0x0000              <<< permitted arp*
> > *permit mac any any 0xAAAA 0x0000 *            *<<< **permitted **stp for
> > dot1q trunks*
> >
> > mac access-map LAB2-26 10
> > match mac address MAC
> > action forward
> > mac access-map LAB2-26 20
> > match ip address 100
> > action forward
> > mac access-map LAB2-26 30
> > action drop
> >
> > vlan filter LAB2-26 vlan-list 12
> >
> >
> >
> >
> >
> > looking further into spanning-tree....
> >
> >
> >
> >
> > *Cat3550-1#show spanning-tree vlan 12*
> >
> > VLAN0012
> >   Spanning tree enabled protocol ieee
> >   Root ID    Priority    32780
> >              Address     0016.c8cf.8d80
> >              This bridge is the root
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >
> >   Bridge ID  Priority    32780  (priority 32768 sys-id-ext 12)
> >              Address     0016.c8cf.8d80
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >              Aging Time 300
> >
> > Interface           Role Sts Cost      Prio.Nbr Type
> > ------------------- ---- --- --------- --------
> > --------------------------------
> > Gi0/1               Desg FWD 4         128.1    P2p
> > Fa0/1               Desg FWD 19        128.3    P2p
> > Fa0/2               Desg FWD 19        128.4    P2p
> > Po12                Desg FWD 12        128.144  P2p
> > Po13                Desg FWD 12        128.152  P2p
> > Po14                Desg FWD 12        128.160  P2p
> >
> >
> >
> >
> >
> > *Cat3560-2#show spanning-tree vlan 12*
> >
> > VLAN0012
> >   Spanning tree enabled protocol ieee
> >   Root ID    Priority    32780
> >              Address     0016.c8bc.1100
> >              This bridge is the root
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >
> >   Bridge ID  Priority    32780  (priority 32768 sys-id-ext 12)
> >              Address     0016.c8bc.1100
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >              Aging Time 300
> >
> > Interface           Role Sts Cost      Prio.Nbr Type
> > ------------------- ---- --- --------- --------
> > --------------------------------
> > Gi0/1               Desg FWD 4         128.1    P2p
> > Po12                Desg FWD 12        128.144  P2p
> > Po23                Desg FWD 12        128.232  P2p
> > Po24                Desg FWD 12        128.240  P2p
> >
> >
> >
> > *cat1*
> > VLAN0012         32780 0016.c8cf.8d80         0    2   20  15
> >
> > *cat2*
> > VLAN0012         32780 0016.c8bc.1100         0    2   20  15
> >
> >
> > *so both switches think there the root for vlan 12*
> >
> >
> >
> > resolved by issuing
> >
> > *Cat3550-1(config)#spanning-tree vlan 12 root primary*
> >
> >
> >
> >
> >
> > but why does the election not agree when cat2 bridge id is lower
> (priority
> > is default) obviously cat 2 tries to become the root by right, but then
> why
> > does cat1?
> >
> >
> > *Bridge ID's*
> > *
> > *
> > *cat 1 vlan 12*
> > 0016.c8cf.8d80
> > *
> > *
> > *cat 2 vlan 12*
> > 0016.c8bc.1100     *<<<<---- should be the winner & IS when no mac
> > access-list/vlan filter is applied*
> >
> >
> > looking further into vlan 12
> >
> >
> > *---------------WITH MAC ACCESS-LIST & ROOT PRIORITY PRIMARY SET ON
> > CAT1-----------------*
> >
> >
> > *debugging whilst this is happening*
> >
> > 05:25:34: STP: VLAN0012 heard root 32780-0016.c8cf.8d80 on Po12
> > 05:25:34: STP(12) port Po12 supersedes 19
> >
> >
> > *Cat3550-1#show spanning-tree vlan 12*
> >
> > VLAN0012
> >   Spanning tree enabled protocol ieee
> >   Root ID    Priority    24588
> >              Address     0016.c8cf.8d80
> >              This bridge is the root
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >
> >   Bridge ID  Priority    24588  (priority 24576 sys-id-ext 12)
> >              Address     0016.c8cf.8d80
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >              Aging Time 300
> >
> > Interface           Role Sts Cost      Prio.Nbr Type
> > ------------------- ---- --- --------- --------
> > --------------------------------
> > Gi0/1               Desg FWD 4         128.1    P2p
> > Fa0/1               Desg FWD 19        128.3    P2p
> > Fa0/2               Desg FWD 19        128.4    P2p
> > *Po12                Desg FWD 12        128.144  P2p *
> > Po13                Desg FWD 12        128.152  P2p
> >
> >
> > *Cat3560-2#show spanning-tree vlan 12*
> >
> > VLAN0012
> >   Spanning tree enabled protocol ieee
> >   Root ID    Priority    24588
> >              Address     0016.c8cf.8d80
> >              Cost        4
> >              Port        1 (GigabitEthernet0/1)
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >
> >   Bridge ID  Priority    32780  (priority 32768 sys-id-ext 12)
> >              Address     0016.c8bc.1100
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >              Aging Time 300
> >
> > Interface           Role Sts Cost      Prio.Nbr Type
> > ------------------- ---- --- --------- --------
> > --------------------------------
> > Gi0/1               Root FWD 4         128.1    P2p
> > *Po12                Altn BLK 12        128.144  P2p *
> > Po23                Desg FWD 12        128.232  P2p
> > Po24                Desg FWD 12        128.240  P2p
> >
> >
> >
> >
> >
> > *-------------------------------WITHOUT MAC ACCESS-LIST & WITHOUT **ROOT
> > PRIORITY PRIMARY SET ON CAT1-**------------*
> >
> >
> > *Cat3550-1#show spanning-tree vlan 12*
> >
> > VLAN0012
> >   Spanning tree enabled protocol ieee
> >   Root ID    Priority    32780
> >              Address     0016.c8bc.1100
> >              Cost        4
> >              Port        1 (GigabitEthernet0/1)
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >
> >   Bridge ID  Priority    32780  (priority 32768 sys-id-ext 12)
> >              Address     0016.c8cf.8d80
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >              Aging Time 15
> >
> > Interface           Role Sts Cost      Prio.Nbr Type
> > ------------------- ---- --- --------- --------
> > --------------------------------
> > Gi0/1               Root FWD 4         128.1    P2p
> > Fa0/1               Desg FWD 19        128.3    P2p
> > Fa0/2               Desg FWD 19        128.4    P2p
> > *Po12                Altn BLK 12        128.144  P2p *
> > Po13                Desg FWD 12        128.152  P2p
> > Po14                Desg FWD 12        128.160  P2p
> >
> >
> > *Cat3560-2#show spanning-tree vlan 12*
> >
> > VLAN0012
> >   Spanning tree enabled protocol ieee
> >   Root ID    Priority    32780
> >              Address     0016.c8bc.1100
> >              This bridge is the root
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >
> >   Bridge ID  Priority    32780  (priority 32768 sys-id-ext 12)
> >              Address     0016.c8bc.1100
> >              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> >              Aging Time 15
> >
> > Interface           Role Sts Cost      Prio.Nbr Type
> > ------------------- ---- --- --------- --------
> > --------------------------------
> > Gi0/1               Desg FWD 4         128.1    P2p
> > *Po12                Desg FWD 12        128.144  P2p *
> > Po23                Desg FWD 12        128.232  P2p
> > Po24                Desg FWD 12        128.240  P2p
> >
> >
> >
> > *+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*
> > *debugging on CAT2 whilst mac access-list is applied to CAT1 & NO
> > **spanning-tree
> > vlan 12 root primary*
> >
> > 05:25:34: STP: VLAN0012 heard root 32780-0016.c8cf.8d80 on Po12
> > 05:25:34: STP(12) port Po12 supersedes 19
> >
> > here's my thinking....
> > cat1 says my cost is 12 for vlan 12 via Po12 ; cat2 relays this message
> > saying 12 supersedes 19 but then where does it get cost of 19 from?
> > *+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*
> > *
> > *
> >
> >
> > what gives i'm confused.com , I know I can resolve the above by running
> > root primary for vlan 12 on CAT1 but need to understand why this default
> > behaviour as this lab task clearly asks that I implement this mac
> > access-list, would this happen in the IE lab ?
> >
> >
> > Tony
> > _______________________________________________
> > 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
> >
> > http://onlinestudylist.com/mailman/listinfo/ccie_rs
> >
> _______________________________________________
> 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
>
> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>
_______________________________________________
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