Switching STP using vIOS-L2
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06-24-2020 11:49 PM
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?
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06-25-2020 12:34 AM
Hello,
could be a bug in IOSv2. What exactly do you have configured, what does your topology look like ?
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06-25-2020 03:13 AM
Attached my topology:
4 Switches ,VLANs, VTP (All 4 switches are on Server mode), Trunk between switches , STP.
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06-25-2020 05:53 AM - edited 06-25-2020 05:54 AM
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
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
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06-25-2020 07:18 AM - edited 06-25-2020 07:19 AM
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 ).
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06-25-2020 11:29 AM - edited 06-25-2020 11:32 AM
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
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06-26-2020 01:10 AM
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.
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06-29-2020 08:51 AM
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
