Solved: STP Linksys Cisco

osgpcqosg · ‎11-16-2010

Hi,

I'm trying to configure un STP between a linksys SRW2024 and a cisco catalyst 3560, I connect the two switch with 2 wires.

I already search here but nothing seems like my problem.

First at all, seems working well, stp block a port.

But if i try to cut some link, sometime work really well and sometime really bad => In fact the both switch are Root !

I have tried to change the mode of the cisco to a more standard way but can't find the right solution for now.

Any suggestions ?

Regards.

PS:Here the conf:

cisco:

     spanning-tree mode rapid-pvst
     spanning-tree loopguard default
     no spanning-tree optimize bpdu transmission
     spanning-tree etherchannel guard misconfig
     spanning-tree vlan 1-1000 priority 0

Linksys:
     spanning-tree
     spanning-tree mode rstp
     spanning-tree priority 4096
     spanning-tree pathcost method short

And the log:
cisco:
 show spanning-tree vlan 140
 VLAN0140
  Spanning tree enabled protocol rstp
  Root ID    Priority    140
             Address     0015.63c4.ef00
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
  Bridge ID  Priority    140    (priority 0 sys-id-ext 140)
             Address     0015.63c4.ef00
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  300 sec

Linksys:
 show spanning-tree 
 Spanning tree enabled mode RSTP
 Default port cost method:  short
  Root ID    Priority    4096
             Address     00:22:6b:bf:f6:eb
             This switch is the root
             Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec
  Times:  hold 1, topology change 35, notification 2
          hello 2, max age 20, forward delay 15

Sebastian Helmer · ‎11-20-2010

Hi Vincent,

the both Spanning-tree modes are not compatible.

change the mode on both switches to the same at least.

I know a nice discussen, maybe it is also interessted for you:

https://learningnetwork.cisco.com/message/81575

regards,

Sebastian

View solution in original post

Sebastian Helmer · ‎11-20-2010

Hi Vincent,

the both Spanning-tree modes are not compatible.

change the mode on both switches to the same at least.

I know a nice discussen, maybe it is also interessted for you:

https://learningnetwork.cisco.com/message/81575

regards,

Sebastian

osgpcqosg · ‎03-06-2012

Hi Sebastian,

First at all, sorry for the delay, just have some time to test it again.

You're obviously right.

The option I have:

Cisco:(config)#spanning-tree mode ?

mst Multiple spanning tree mode

pvst Per-Vlan spanning tree mode

rapid-pvst Per-Vlan rapid spanning tree mode

Linksys:(config)# spanning-tree mode

stp Specify IEEE 802.1D Spanning Tree Protocol

rstp Configure IEEE 802.1W Rapid Spanning Tree Protocol

mstp Configure IEEE 802.1S Multiple Spanning Tree Protocol

In the link you send me:

Based on the original IEEE 802.1w standard, RSTP can have multiple VLANs 10, 20, 20 and 40 but will only have a

single instance of spanning tree running for all VLANs, just like the Traditional STP 802.1D (CST). The IEEE 802.1w RSTP standard does not support multiple instances of STP, it does support multiple VLANs. Cisco's version of RSTP, known as RPVST+, combines RSTP with PVST+, and uses a separate instance of spanning tree for each VLAN, just like their proprietary PVST+.

For now, thought I could try the mstp/mst solutions, but I will keep it simple,

so I will try the rapid-pvst/stp solution, and I will comment you.

Best regards.

osgpcqosg · ‎07-10-2012

So, a lot of time later, but with the homework done.

The Cisco "rapid-pvst" and the linksys "stp" mode are fully compatible. (Sure with the 14 second of delay).

Best regards.

Configuration used:

Cisco:

spanning-tree mode rapid-pvst

spanning-tree loopguard default

no spanning-tree optimize bpdu transmission

spanning-tree etherchannel guard misconfig

spanning-tree extend system-id

spanning-tree vlan 1-1000 priority 0

!

interface FastEthernet0/9

description lliure

switchport access vlan 10

switchport mode access

spanning-tree portfast

spanning-tree link-type point-to-point

!

interface FastEthernet0/10

description lliure

switchport access vlan 10

switchport mode access

spanning-tree portfast

spanning-tree link-type point-to-point

Linksys:

spanning-tree

spanning-tree priority 4096

spanning-tree pathcost method short

interface range ethernet g(11-24)

spanning-tree portfast

exit

interface range ethernet g(9-10)

spanning-tree link-type point-to-point

Exemple:

# sh spanning-tree

Spanning tree enabled mode STP

Default port cost method: short

Root ID Priority 10

Address 00:15:63:c4:ef:00

Cost 19

Port g9

sw-test01#sh spanning-tree vlan 10

VLAN0010

Spanning tree enabled protocol rstp

Root ID Priority 10

Address 0015.63c4.ef00

This bridge is the root

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

Bridge ID Priority 10 (priority 0 sys-id-ext 10)

Address 0015.63c4.ef00

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

Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type

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

Fa0/8 Desg FWD 19 128.10 P2p Edge

Fa0/9 Desg FWD 19 128.11 P2p Peer(STP)

Fa0/10 Desg FWD 19 128.12 P2p Peer(STP)