Q-in-Q VLAN config/scenario question...

[dvtestguy]

Will this config/scenario work?

I have two connections between a 6506 and 4948. (VLAN 800 an an Outer VLAN, and 801 as an Inner VLAN)

1) Is my primary VTP Trunk.
2) Trunk Port <-> Tunnel Port for Q-in-Q.

Internet -- 6506 (Trk Port)--(Trk Port) 4948 -- Test Device
(Trk Port)--(Tun Port) 4948

6506
Cisco6500IOS#sh run int g3/1
interface GigabitEthernet3/1
description Trunk Port to Cisco 4948
switchport
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-7,9-11,13-799,801-4094
switchport mode trunk
switchport nonegotiate
spanning-tree portfast trunk
end

Cisco6500IOS#sh run int f4/8
Building configuration...

Current configuration : 169 bytes
!
interface FastEthernet4/8
switchport
switchport access vlan 800
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 800
switchport mode trunk
end

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

4849
interface GigabitEthernet1/47
description trunk to Cisco 6506
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-7,9-11,13-800,802-4094
switchport mode trunk
switchport nonegotiate
spanning-tree portfast trunk
end

Cisco4948#sh run int g1/8
Building configuration...

Current configuration : 147 bytes
!
interface GigabitEthernet1/8
switchport access vlan 801
switchport trunk encapsulation dot1q
switchport mode dot1q-tunnel
no cdp enable

 

[fdurham]

dvtestguy-

That scenerio above will not work with Q-in-Q. The reason is you have to simulate a service provider's network; thus requiring two more switches. hee is the example..

6506-----------(SPSWA)+++++++++++++(SPSWB)----------4849
c6506: Enable trunking like your config above.
SPSWA: Service Provider's switch would turn on dot1q Tunneling and encapsulate your VLANs in a VLAN of their own.
SPWB: Service Provider's switch would also have dot1q tunneling enabled on a port facing your SW to strip off the SP VLAN tag.
4849: Your config above.

Unless I am misunderstanding what your goal is.

Let me know.

Frank

 

[dvtestguy]

Hey Frank,

I thought the 4948 would peel off VLAN 800 and send VLAN 800 through supporting this feature? I'm trying to assure next-hop VLAN tagging, and will need multi-hop down the raod when we get more switches.

 

[fdurham]

dvtestguy-

I see your configure, a little cleare now. By looking at it, int g 3/1 on the 6506 is connected to int g 1/47 on the 4948. That looks like your classic 802.1Q trunking enabled. Then I see int g 4/8 on the 6506 connected to int g 1/8 on the 4948. That looks like one half of the Q-in-Q setup. Which would send VLAN 800 to the 4948 which then would ecapsulate it into VLAN 801. Thats looks good, but there isn't another switch to strip that VLAN 801 tag off to access your VLAN800.

Frank

 

[dvtestguy]

I have a test device that will simulate double VLANS, connected to the 4948 trunked to the 6506 and then out to the internet/cloud.

Test Device -- 4948 -- 6506 --7513 NAT'ing out to the internet.

I was concerned that even though the 4948 will strip off VLAN 801, then forward VLAN 800 out to the internet would be a realistic scenario.

 

[fdurham]

Ok got it.

Well your config looks good. Just looks like its up to the test device to confirm it.

Frank