Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

RAPID SPANNING TREE

--begin ciscomoderator note-- The following post has been edited to remove potentially confidential information. Please refrain from posting confidential information on the site to reduce security risks to your network. -- end ciscomoderator note --

Hi

I have got 2 switches in 2 different buildings connected via a laser link which connects to both switches on a point to point link.I run spanning tree over the link as if it were one network.A bridge if you like.I have also got a wireless Lan access point at the one building and a client bridge at the other building.The 2 devices are also conencted to the 2 switches.The problem I am having is that the wirless needs to be used a fast rapid spanning tree backup in case the laser link fails.I have configured both switches with spanning-tree mode rapid-pvst.The one switch is the the root bridge.When i shut the laser link down to test my wirless backup with rapid spanning tree it does not seem to work although on the switch I can ping the wirless bridge and access point.I just cant ping any device or the switch on the other side......

I got this all to work in a test environment without any other devices connected to the switches,but now that I have got it all on the live network it does not want to use the alternative path down the wirless when I bring the laser down.The wirless has a cost of 100 and the laser has a cost of 19.Am I missing something out in my configuration.

My config os the root bridge switch is below....The other switch is the same besides the ip address and priority.I have also attache the show spanning tree command.Any help or guidance will be much appreciated.

spanning-tree mode rapid-pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

spanning-tree vlan 1 priority 61440

!

!

interface FastEthernet0/1

--More-- no ip address

!

interface FastEthernet0/2

no ip address

!

interface FastEthernet0/3

no ip address

!

interface FastEthernet0/4

no ip address

!

interface FastEthernet0/5

no ip address

!

interface FastEthernet0/6

no ip address

!

interface FastEthernet0/7

no ip address

!

interface FastEthernet0/8

no ip address

!

--More-- interface FastEthernet0/9

no ip address

!

interface FastEthernet0/10

no ip address

!

interface FastEthernet0/11

no ip address

!

interface FastEthernet0/12

no ip address

!

interface FastEthernet0/13

no ip address

!

interface FastEthernet0/14

no ip address

!

interface FastEthernet0/15

no ip address

!

interface FastEthernet0/16

no ip address

--More-- !

interface FastEthernet0/17

no ip address

!

interface FastEthernet0/18

no ip address

!

interface FastEthernet0/19

no ip address

!

interface FastEthernet0/20

no ip address

!

interface FastEthernet0/21

no ip address

!

interface FastEthernet0/22

no ip address

!

interface FastEthernet0/23

no ip address

!

interface FastEthernet0/24

--More-- no ip address

!

interface FastEthernet0/25

no ip address

!

interface FastEthernet0/26

no ip address

!

interface FastEthernet0/27

no ip address

!

interface FastEthernet0/28

no ip address

!

interface FastEthernet0/29

no ip address

!

interface FastEthernet0/30

no ip address

!

interface FastEthernet0/31

no ip address

!

--More-- interface FastEthernet0/32

no ip address

!

interface FastEthernet0/33

no ip address

!

interface FastEthernet0/34

no ip address

!

interface FastEthernet0/35

no ip address

!

interface FastEthernet0/36

no ip address

!

interface FastEthernet0/37

no ip address

!

interface FastEthernet0/38

no ip address

!

interface FastEthernet0/39

no ip address

--More-- !

interface FastEthernet0/40

no ip address

!

interface FastEthernet0/41

no ip address

!

interface FastEthernet0/42

no ip address

!

interface FastEthernet0/43

no ip address

!

interface FastEthernet0/44

no ip address

!

interface FastEthernet0/45

no ip address

!

interface FastEthernet0/46

no ip address

duplex full

speed 100

--More-- !

interface FastEthernet0/47

no ip address

duplex full

speed 100

!

interface FastEthernet0/48

no ip address

!

interface GigabitEthernet0/1

no ip address

!

interface GigabitEthernet0/2

no ip address

!

interface Vlan1

ip address 10.98.7.236 255.255.248.0

no ip route-cache

!

ip default-gateway 10.98.7.254

ip http server

!

snmp-server engineID local xxxxxxxxxxxxxxxxxxxxxxxxxxxx

--More-- snmp-server community xxxxxxxxxxxxxxxxx RO

sho spann

NLONL03S02#sho spanning-tree

VLAN0001

Spanning tree enabled protocol rstp

Root ID Priority 10

Address 0005.dcc0.b1c0

Cost 19

Port 12 (FastEthernet0/12)

Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 61441 (priority 61440 sys-id-ext 1)

Address 000b.fd7f.1080

Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Aging Time 300

Interface Role Sts Cost Prio.Nbr Type

---------------- ---- --- --------- -------- --------------------------------

Fa0/3 Desg FWD 19 128.3 P2p

Fa0/4 Desg FWD 100 128.4 Shr

Fa0/5 Desg FWD 19 128.5 P2p

Fa0/6 Desg FWD 19 128.6 P2p

Fa0/7 Desg FWD 19 128.7 P2p

Fa0/8 Desg FWD 19 128.8 P2p

Fa0/9 Desg FWD 19 128.9 Shr

--More--

Interface Role Sts Cost Prio.Nbr Type

---------------- ---- --- --------- -------- --------------------------------

Fa0/10 Desg FWD 19 128.10 Shr

Fa0/12 Root FWD 19 128.12 P2p Peer(STP)

Fa0/13 Desg FWD 19 128.13 P2p

Fa0/14 Desg FWD 19 128.14 P2p

Fa0/15 Desg FWD 19 128.15 P2p

Fa0/16 Desg FWD 19 128.16 P2p

Fa0/17 Desg FWD 19 128.17 P2p

Fa0/18 Desg FWD 19 128.18 P2p

Fa0/19 Desg FWD 19 128.19 P2p

Fa0/20 Desg FWD 19 128.20 P2p

Fa0/21 Desg FWD 19 128.21 P2p

Fa0/22 Desg FWD 19 128.22 P2p

Fa0/23 Desg FWD 19 128.23 P2p

Fa0/25 Desg FWD 19 128.25 P2p

Fa0/27 Desg FWD 19 128.27 P2p

Fa0/28 Desg FWD 19 128.28 Shr

Fa0/29 Desg FWD 19 128.29 P2p

Fa0/31 Desg FWD 100 128.31 Shr

Fa0/32 Desg FWD 19 128.32 P2p

Fa0/33 Desg FWD 19 128.33 P2p

Fa0/34 Desg FWD 19 128.34 Shr

Fa0/35 Desg FWD 19 128.35 P2p

Fa0/36 Desg FWD 19 128.36 P2p

--More--

Interface Role Sts Cost Prio.Nbr Type

---------------- ---- --- --------- -------- --------------------------------

Fa0/37 Desg FWD 19 128.37 P2p

Fa0/38 Desg FWD 100 128.38 Shr

Fa0/39 Desg FWD 19 128.39 P2p

Fa0/40 Desg FWD 100 128.40 Shr

Fa0/41 Desg FWD 19 128.41 P2p

Fa0/42 Desg FWD 19 128.42 Shr

Fa0/43 Desg FWD 19 128.43 P2p

Fa0/44 Desg FWD 100 128.44 Shr

Fa0/45 Desg FWD 100 128.45 Shr

Fa0/46 Desg FWD 19 128.46 P2p

Fa0/47 Desg FWD 19 128.47 P2p

Fa0/48 Desg FWD 100 128.48 P2p

Gi0/1 Desg FWD 4 128.49 P2p Peer(STP)

NLONL03S02#

Outline | Subscribe |

Bookmark | E-Mail this Message

ward - COMDISCO

Sep 3, 2003, 3:25pm PST

Please note that port 47 is the laser and port 48 the wirless link.

Thanks

2 REPLIES
Silver

Re: RAPID SPANNING TREE

Most probably you are running into SPT problem. Have a look of the following links for troubleshooting

http://www.cisco.com/en/US/products/hw/wireless/ps458/products_tech_note09186a00800a86d7.shtml

http://www.cisco.com/warp/public/473/146.html

New Member

Re: RAPID SPANNING TREE

Hi,

What does show spanning-tree int mod/port on the non-root switch say? It should be in blk state when the laser link is up ... and, go from blk to fwd when the laser link fails.

Also, check the show interface mod/port on both ends and make sure that the laser link is in down/down state.

-Robert

187
Views
0
Helpful
2
Replies
CreatePlease login to create content