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Spanning tree issue on C1111 router

WilsonCheng
Level 1
Level 1

Spanning tree was configured and enabled on C1111 router, but show spanning tree shows no spanning tree information as below. Does anyone know what the issue is and how to fix it? Thank you.

 

router#sh run | s spanning
spanning-tree extend system-id
spanning-tree vlan 1,599,990 priority 61440
 
router#sh ip int brief
Interface              IP-Address      OK? Method Status                Protocol
GigabitEthernet0/0/0   #####    YES NVRAM  up                    up      
GigabitEthernet0/0/1   unassigned      YES NVRAM  administratively down down    
GigabitEthernet0/1/0   unassigned      YES unset  up                    up      
GigabitEthernet0/1/1   unassigned      YES unset  administratively down down    
GigabitEthernet0/1/2   unassigned      YES unset  administratively down down    
GigabitEthernet0/1/3   unassigned      YES unset  up                    up      
Vlan1                  unassigned      YES unset  administratively down down    
Vlan599                10.250.182.226  YES NVRAM  up                    up      
Vlan990                10.41.98.2      YES NVRAM  up                    up      

router#sh spanning-tree
No spanning tree instance exists.

router#sh spanning-tree sum
Switch is in rapid-pvst mode
Root bridge for: none
EtherChannel misconfig guard            is enabled
Extended system ID                      is enabled
Portfast Default                        is disabled
PortFast BPDU Guard Default            is disabled
Portfast BPDU Filter Default           is disabled
Loopguard Default                      is disabled
UplinkFast                              is disabled
BackboneFast                            is disabled
Configured Pathcost method used is short

Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
Total                        0         0        0          0          0
23 Replies 23

Hello

Just noticed you have no interfaces in either of the vlans  the two ports that are active are in vlan 1 and that’s admin down  either assign one of the ports to those vlans or enable vlan1


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Kind Regards
Paul

vlan 1 is the default vlan for all ports. we don't use it, so shut it down.
vlan 599 and vlan 990 are on trunk port g0/1/0 already. We don't need to
assign them to the access port.

router#sh int trunk

Port Mode Encapsulation Status Native vlan
Gi0/1/0 on 802.1q trunking 990

Port Vlans allowed on trunk
Gi0/1/0 1-4094

Port Vlans allowed and active in management domain
Gi0/1/0 1,599,990

Port Vlans in spanning tree forwarding state and not pruned
Gi0/1/0 1,599,990

Hello

 


@WilsonCheng wrote:
vlan 599 and vlan 990 are on trunk port g0/1/0 already. We don't need to
assign them to the access port.

Granted but we are discussing a rtr here not a definitive switching device, we could be well looking at buggy software,  
You could try reapplying or changing the stp mode to see if that helps and as vlan 1 is being allowed over the trunk enable it just to see?

 

Gi0/1/1, Gi0/1/2 = down state
g0/1/0 = trunk (native vlan 990)
gig0/0/0 = i assume is routed 
gig0/1/3 <   ??? 


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

emurray
Level 1
Level 1

I think this router does not support Spanning-Tree. It does support layer 3 port-channel, but in the documentation, it does not mention anything of spanning-tree or any of 802.1D, 802.1W, 802.1s standards on the LAN ports, it does not even support layer 2 port-channels. 

 

https://www.cisco.com/c/en/us/products/collateral/routers/1000-series-integrated-services-routers-isr/datasheet-c78-739512.html 

 

I do have the C1111-4p and I was surprised when I wanted to do layer 2 port-channel on the LAN ports and it was not supported. 

 

 

Hello @emurray 

If this is correct that would do be the reason; I’m surprised it lets you create l2 features if it doesn’t support them.


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

In prior images,  the commands were not there. I just notice that in my latest upgrade, I have active/passive options for LACP mode in channel-group spanning-tree but they were not there in version 16, and last year when I tried, I couldn't find any of the commands available. Now only has LACP options, It does not have PAGP options.

 

I found in my research last year, a thread here stating the router does not have the power to do all those functions. 

 

Maybe version 17 have the commands now, but is still incapable of supporting spanning-tree

 

 

 

k-baba
Level 1
Level 1

I guess this relate to "vlan database".

To check it, execute following commands from global command prompt.

vlan database

show

rasmus.elmholt
Level 7
Level 7

That is a strange thing about the C1111. If I look at show span then I don't get any output until I activate rapid-PVST as shown here.

R1#show vlan brie

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Gi0/1/0, Gi0/1/1, Gi0/1/2, Gi0/1/3, Gi0/1/4, Gi0/1/5
3    Firewall-Interconnect            active    Gi0/1/6

R1#show span

No spanning tree instance exists.
R1#conf t             
Enter configuration commands, one per line.  End with CNTL/Z.
R1(config)#spanning-tree mode rapid-pvst 
Warning: Changing STP mode can disrupt the traffic and make system unstable
Recommend to change STP mode only during maintenance window
R1(config)#do show span
G0:VLAN0003
  Spanning tree enabled protocol rstp
  Root ID    Priority    32771
             Address     f80f.6f6a.40f1
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32771  (priority 32768 sys-id-ext 3)
             Address     f80f.6f6a.40f1
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  300 sec

Interface           Role Sts Cost      Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi0/1/6             Desg LRN 4         128.15   P2p 
Gi0/1/7             Desg LRN 4         128.16   P2p 

k-baba
Level 1
Level 1

It seems to be very strange because the initial post of this thread has following 

router#sh spanning-tree sum
Switch is in rapid-pvst mode

If you have output of "show spanning-tree summary" before entering command for rapid-pvst mode, it may help to clarify the situation.

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