you need to change the mode

moiz.khan1 · ‎06-21-2016

Hi

I am trying to set up a STP with 2 3560 switches and I have 2 uplinks, I have made the trunk on both links, I am trying to figure out how I can make 1 link amber for both ports on each switch, I am not sure how to do that,

The end goal is so when I remove the active (green) links the amber link will turn green in 30 seconds.

Thanks

Mark Malone · ‎06-21-2016

Hi

If you have 2 trunks and you want one trunk to be less preferred access the interface and set the spanning-tree cost 5000 that will put it into blocking as it cost will be higher than the other trunk,only if the lower cost link fails will this become active

The other option is bundle the links together in a layer 2 port-channel , so if one fails the other is still active, this is usually the more preferred option as you dont have redundant links but both active

If you want your STP to speed up in terms of convergence look at the mode your using , depending on platform you may have the option for rstp or rpvst+

int gx/x

spanning-tree cost 5000

moiz.khan1 · ‎06-21-2016

will that make 1 link green(active-forwarding) and the other amber(blocked-standby)? because thats what im trying to accomplish, i have tried both ways but that doesnt seem to get the port colours i want and active link and standby link

Mark Malone · ‎06-21-2016

Yes setting the STP cost will force 1 of the links to go blocking , 1 should be blocking already automatically if there is only 2 though to prevent a loop if they are directly connected equal links between 2 switches

whats does your show spanning-tree blockedports command provide and show spanning-tree

moiz.khan1 · ‎06-21-2016

new#show spanning-tree blocke <--- root switch 3560

Name Blocked Interfaces List
-------------------- ------------------------------------

Number of blocked ports (segments) in the system : 0

new#sh span <-- root switch 3560

VLAN0005
Spanning tree enabled protocol ieee
Root ID    Priority    28677
             Address     001a.e3cd.9e80
             This bridge is the root
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28677 (priority 28672 sys-id-ext 5)
             Address     001a.e3cd.9e80
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/24           Desg FWD 19        128.26   P2p
Fa0/26           Desg FWD 5000      128.30   P2p

VLAN0010
Spanning tree enabled protocol ieee
Root ID    Priority    28682
             Address     001a.e3cd.9e80
             This bridge is the root
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28682 (priority 28672 sys-id-ext 10)
             Address     001a.e3cd.9e80
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/24           Desg FWD 19        128.26   P2p
Fa0/26           Desg FWD 5000      128.30   P2p

VLAN0015
Spanning tree enabled protocol ieee
Root ID    Priority    28687
             Address     001a.e3cd.9e80
             This bridge is the root
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28687 (priority 28672 sys-id-ext 15)
             Address     001a.e3cd.9e80
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/24           Desg FWD 19        128.26   P2p
Fa0/26           Desg FWD 5000      128.30   P2p

VLAN0020
Spanning tree enabled protocol ieee
Root ID    Priority    28692
             Address     001a.e3cd.9e80
             This bridge is the root
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28692 (priority 28672 sys-id-ext 20)
             Address     001a.e3cd.9e80
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/24           Desg FWD 19        128.26   P2p
Fa0/26           Desg FWD 5000      128.30   P2p

second#sh span <--- regular 3560 switch

VLAN0005
Spanning tree enabled protocol ieee
Root ID    Priority    28677
             Address     001a.e3cd.9e80
             Cost        19
             Port        28 (GigabitEthernet0/28)
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28677 (priority 28672 sys-id-ext 5)
             Address     0023.abcd.b900
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/26           Altn BLK 5000      128.26   P2p
Gi0/28           Root FWD 19        128.28   P2p

VLAN0010
Spanning tree enabled protocol ieee
Root ID    Priority    28682
             Address     001a.e3cd.9e80
             Cost        19
             Port        28 (GigabitEthernet0/28)
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28682 (priority 28672 sys-id-ext 10)
             Address     0023.abcd.b900
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/26           Altn BLK 5000      128.26   P2p
Gi0/28           Root FWD 19        128.28   P2p

VLAN0015
Spanning tree enabled protocol ieee
Root ID    Priority    28687
             Address     001a.e3cd.9e80
             Cost        19
             Port        28 (GigabitEthernet0/28)
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28687 (priority 28672 sys-id-ext 15)
             Address     0023.abcd.b900
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/26           Altn BLK 5000      128.26   P2p
Gi0/28           Root FWD 19        128.28   P2p

VLAN0020
Spanning tree enabled protocol ieee
Root ID    Priority    28692
             Address     001a.e3cd.9e80
             Cost        19
             Port        28 (GigabitEthernet0/28)
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority    28692 (priority 28672 sys-id-ext 20)
             Address     0023.abcd.b900
             Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/26           Altn BLK 5000      128.26   P2p
Gi0/28           Root FWD 19        128.28   P2p

second#show spanning-tree blocke   <-- regular 3560 switch

Name                 Blocked Interfaces List
-------------------- ------------------------------------
VLAN0005             Gi0/26
VLAN0010             Gi0/26
VLAN0015             Gi0/26
VLAN0020             Gi0/26

Number of blocked ports (segments) in the system : 4

moiz.khan1 · ‎06-21-2016

im looking to get 1 link with green ports on both ports and the other 1 standby blocked link both ports being amber

Mark Malone · ‎06-21-2016

Its blocking all vlans on the non root switch G0/26 with cost of 5000 so that link is redundant now between the 2 switches until the other physical link fails or you pull it out

moiz.khan1 · ‎06-22-2016

i did that but its not making the LEDs amber,

Mark Malone · ‎06-22-2016

That's because 1 switch is a root switch and all the ports are designated forwarding by default so it will only block the far end with pvst , the link is still redundant

moiz.khan1 · ‎06-22-2016

id like to make 1 link green LED and the other link being amber, with a active/standby link so when i pull the active link out, the standby link takes over after 30 seconds, id like to express that both ports should be amber on each port for the link, and green for the other link, how do i achieve this?

Mark Malone · ‎06-22-2016

Your links are active/standby in STP , you may not be able to have a amber LED on root bridge by feature design as the ports are designated forwarding by default in STP

moiz.khan1 · ‎06-22-2016

i made a command "spanning-tree mode pvst' how can i reverse this command? i now have all 4 lights green where there should be only 3 by default and 1 amber

Mark Malone · ‎06-22-2016

you need to change the mode back to what you were using before , question mark aftee the spanning-tree mode ? will show you what option are available on your platform if you dont know what you were using before

spanning-tree mode ?

Setting up Spanning Tree active/standby link