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Switching STP using vIOS-L2

medharrak
Level 1
Level 1

I'm trying to configure STP using vIOS-L2 on GNS3, the loop works only with VLAN1 , for the other VLANs , All the switches display "This bridge is the root"

Any idea about the issue?

7 Replies 7

Hello,

 

could be a bug in IOSv2. What exactly do you have configured, what does your topology look like ?

Attached my topology:

4 Switches ,VLANs, VTP (All 4 switches are on Server mode), Trunk between switches , STP.

 

Hello

 


@medharrak wrote:

I'm trying to configure STP using vIOS-L2 on GNS3, the loop works only with VLAN1 , for the other VLANs , All the switches display "This bridge is the root"


Make sure all vlans reside on each switch and are they able to traverse the trunks- Also manually set your primary switch to be the stp root
spanning-tree vlan 1-4094 priority 0


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Kind Regards
Paul

VTP works as expected and propagate created VLAN on "DLS1" to all other Switches.
Also I did configure the DLS1 as root primary (spanning-tree vlan 100,200 root primary)
and "DLS2" as backup (spanning-tree 100,200 root secondary ).

hello


@medharrak wrote:

VTP works as expected and propagate created VLAN on "DLS1" to all other Switches.
Also I did configure the DLS1 as root primary (spanning-tree vlan 100,200 root primary)
and "DLS2" as backup (spanning-tree 100,200 root secondarI posted previoulsy y ).


Specifying the stp root with the root primary/secondary macro won't preempt was if/when an additional switch comes on line with a much preferred bridge id a better way to be more deterministic about stp root placement would use a manual setting as I posted previously also given how flaky CML is it could be the stp root macro isnt work correctly so try/test that command instead.


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

Hi,
I did change the default encapsulation on Uplinks from ISL to 802.1q and it worked just fine .I don't know why it wasn't working with ISL.

I did change Cisco IOSvL2 to vios_l2-adventerprisek9-m.vmdk.SSA.152-4.0.55.E

and it's working fine.

there is a bug with the version vios_l2-adventerprisek9-m-15.2-2017032.qcow2

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