STP over multiple vlans, over EoMPLS on a ME3600

[jsmottram1]

I believe this is a feature which is not yet available, but wanted to confirm if this was a know issue or other ways around this exist.

The setup is this..

Customer port - ME 3600 - CORE MPLS - ME 3600 - Customer Port

Between the ME3600's we setup EoMPLS connections to transport the customer vlans over, the issue is we have not found a way to send over and transport muliple vlans in the same xconnect and pass over BPDU's.

For some of these we can just send vlan over, this works fine with STP, using the below config (for vlan 100)

'interface GigabitEthernet0/1

service instance 100 ethernet

encapsulation dot1q 100

l2protocol tunnel cdp stp

rewrite ingress tag pop 1 symmetric

bridge-domain 100

int vlan 100

xconnect 192.168.2.1 100 encapsulation mpls'

If we need to send multiple over we can use the below config and everything work, apart from STP for (Vlans 200-250)

'interface GigabitEthernet0/2

service instance 200 ethernet

encapsulation dot1q 200-250

xconnect 192.168.2.1 200'

We have tried all other versions to do this, including the below, this seems to allow BPDU's to pass but has issues with other protocols like HSRP (vlans 300-350)

'interface GigabitEthernet0/3

service instance 300 ethernet

encapsulation dot1q 300-350

l2protocol tunnel cdp stp

bridge-domain 300

int vlan 300

xconnect 192.168.2.1 300 encapsulation mpls'

This means at present the only way to send muliple vlans is to break them up and do 1 at a time, in there own Xconnect, which is not scalebable.

Any thoughts on this woudl be appreicated, we are on code 15.1(2).

[Mohamed Sobair]

Hello,

May you elaborate more on how exactly your HSRP is not working? we need to understand your current topology, In any way, Your current Setup should tunnel STP, BPDU, VTP  layer-2 protocols.

HSRP uses UDP port 1985 , do you have anything blocks that at the Customer side? Please give us more overview about your exact Scenario and where is your HSRP currently configured? and what verfication you have done to notice that?

Thanks,

Mohamed

[jsmottram1]

Mohamed,

Thanks for your reply.

The question is what is the correct way to be configuring this as to send multiple vlans down a EoMPLS and to tunnel and allow BPDU's to pass, with other traffic.

The scenario I mentioned with HSRP failing, was in effect one which I need to lab up myself and replicate, the issue reported was that the two HSRP hosts could not see each other. I do not know what or if anything else failed, as I did not have time to troubleshoot this. The resolution to this was to change the configuration to a single vlan (like in the first config example) and this worked fine.

The remote setup was the same in all three scenarios, with just the ME config changing, the first configuration example works, but has to be conducted on a vlan by vlan basis, in the 2nd, HSRP works, but BPDU's are not passed, and in the third BPDU's are passed any HSRP is not.

The MPLS setup is quite basic with two Cisco XR devices between the ME Switches.

On the customer side is 6500 Cisco switch, we have replicated issues with BPDU's on various IOS switches, and the single vlan is the only method in which we have been able to get a working solution.

Thanks.

James.

[Mohamed Sobair]

James,

Ok, The below config should be the right one, and really I am not sure whay your HSRP is not working.

'interface GigabitEthernet0/3

service instance 300 ethernet

encapsulation dot1q 300-350

l2protocol tunnel cdp stp

bridge-domain 300

int vlan 300

xconnect 192.168.2.1 300 encapsulation mpls'

Could you perhaps send us the config of your HSRP on both devices, and to double check your EoMPLS connection is up? perhaps thers is a misconfig from from the customer side.

Regards,

Mohamed

[jsmottram1]

Thanks, I will look to lab this up and see if I can replicate this HSRP issue.

James