Ethernet Switching
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Ethernet Switching

[vQFX] QinQ popping outer and inner tag

[ Edited ]
‎09-04-2019 05:28 AM

Hello!

I'm trying to lab a basic QinQ setup using all in one bundling of C-VLANs from CE1 and CE2 to S-VLAN 1024 between AGN1 and AGN2.

I have attached an image of the topology and the relevant configuration for each device.

 

I have been running ping tests from CE1 to CE2 whilst running wireshark at each physical segment. Between CE1 and AGN1 the frame appears normal, with a C-VLAN tag of 5. Between AGN1 and AGN2 the QinQ appears to be working, as there is an outer tag of 1024, with an inner tag of 5. 

The problem, however, is with the last physical segment, where both the outer and the inner tag are being stripped from the frame, resulting in CE2 receiving an untagged frame.

 

I am really unsure why this is happening as I believe the command output-vlan-map pop should only pop the outer tag right?

 

QinQ-Lab-Topology.png

 

 

CE1:

root@CE1# show vlans 
CUST-NET {
    vlan-id 5;
    l3-interface irb.5;
}
default {
    vlan-id 1;
}

root@CE1# show interfaces xe-0/0/1  
unit 0 {
    family ethernet-switching {
        interface-mode trunk;
        vlan {
            members CUST-NET;
        }
    }
}

root@CE1# show interfaces irb.5 
family inet {
    address 10.0.5.1/24;
}

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

CE2: 

root@CE2# show vlans 
CUST-NET {
    vlan-id 5;
    l3-interface irb.5;
}
default {
    vlan-id 1;
}

root@CE2# show interfaces xe-0/0/1 unit 0 { family ethernet-switching { interface-mode trunk; vlan { members CUST-NET; } } }
root@CE2# show interfaces irb.5 family inet { address 10.0.5.2/24; } ----------------------------- AGN1: root@AGN1# show vlans SERVICE-VLAN { interface xe-0/0/0.1024; interface xe-0/0/1.1024; } default { vlan-id 1; } root@AGN1# show interfaces xe-0/0/0 description "Link to AGN2 (QinQ Trunk)"; flexible-vlan-tagging; encapsulation extended-vlan-bridge; gigether-options { ethernet-switch-profile { tag-protocol-id 0x88a8; } } unit 1024 { vlan-id 1024; } root@AGN1# show interfaces xe-0/0/1 description "Link to CE1 (QinQ Access)"; flexible-vlan-tagging; native-vlan-id 1024; encapsulation extended-vlan-bridge; unit 1024 { vlan-id-list 1-4094; input-vlan-map push; output-vlan-map pop; } ----------------------------- AGN2: root@AGN2# show vlans SERVICE-VLAN { interface xe-0/0/0.1024; interface xe-0/0/1.1024; } default { vlan-id 1; } root@AGN2# show interfaces xe-0/0/0 description "Link to AGN1 (QinQ Trunk)"; flexible-vlan-tagging; encapsulation extended-vlan-bridge; gigether-options { ethernet-switch-profile { tag-protocol-id 0x88a8; } } unit 1024 { vlan-id 1024; } root@AGN2# show interfaces xe-0/0/1 description "Link to CE2 (QinQ Access)"; flexible-vlan-tagging; native-vlan-id 1024; encapsulation extended-vlan-bridge; unit 1024 { vlan-id-list 1-4094; input-vlan-map push; output-vlan-map pop; }

 

 

2 REPLIES 2
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Ethernet Switching

Re: [vQFX] QinQ popping outer and inner tag

‎09-04-2019 09:06 AM

Hi, 

 

I think the outer vlan (1024) is being popped inbound on xe-0/0/0 on AGS2 (vlan normalization), and then the action pop applied to xe-0/0/1 is removing the other vlan-id.  

 

I cannot find a document describing the behavior for QFX (nor I have tried on QFX) but I know it happens on MX and it's called implicit VLAN translation or normalization.  

 

https://www.juniper.net/documentation/en_US/junos/topics/task/configuration/layer-2-vlans-normalized...

 

You might not even need the input and output maps in your set up.  Try removing the maps or maybe this way: 

 

QinQ-1.pngQinQ-2.png

HTH,

 

Yasmin Lara - Juniper Ambassador #QuadE - JNCIE-SP, JNCIE-ENT, JNCIE-DC, JNCIE-SEC
JNCIS-CLOUD, JNCDS-DC, JNCIA-DevOps
Ethernet Switching

Re: [vQFX] QinQ popping outer and inner tag

‎09-05-2019 08:19 AM

Your config looks correct to me. Here's an example for qinq config on QFX. I don't see much of difference 

 

https://kb.juniper.net/InfoCenter/index?page=content&id=KB33838&cat=QFX_SERIES&actp=LIST

 

Let's get "show interface xe-0/0/1.1024" output. This will tell you what action does it take. According to your config, it should be input push 1024, output pop. What do you see? Do you see output "pop pop" ? Don't look to be expected behavior, like a bug.  


Mengzhe Hu
JNCIE x 3 (SP DC ENT)