Thanks Jay! - I had no issues with the configuration below

I will add the following to what you indicated below to ensure that I
understand (I know someone will correct me if I am not ;) )

It will go into err-disabled state if a port enabled for
l2protocol-tunneling receives the Cisco proprietary MAC address which is
generated by ports configured with L2protocol-tunneling - The MAC is flooded
out the all ports that have the same VLAN configured on the
L2protocol-tunneling port including trunks (this prevents loops). You must
prune the VLAN off the trunks to ensure this does not happen. 

If you do not prune the VLAN then you will receive the following: 02:27:38:
%PM-4-ERR_DISABLE: l2ptguard error detected on Fa0/20, putting Fa0/20 in
err-disable state




-----Original Message-----
From: Jay Taylor [mailto:[email protected]] 
Sent: February-19-11 8:52 PM
To: Jason Maynard
Cc: CCIE_RS OnlineStudyList
Subject: Re: [OSL | CCIE_RS] dot1q-tunnel

The only caveat I know of is with l2pt where receiving a l2tp frame will
cause an l2pt enabled port to go err-disable. Doesn't look like that will
happen with either of your scenarios so I think you're good. 

Sent from my iPhone

On Feb 19, 2011, at 7:56 PM, "Jason Maynard" <[email protected]>
wrote:

> I am just looking for confirmation
> 
> 
> 
> Do you require an isolated trunk link when using dot1q-tunnel or do you
just
> need to ensure the VLAN is allowed on the respective trunk?
> 
> 
> 
> For example
> 
> |R1| 0/1 ----- 0/1 |CAT1| 0/21 0/22 ============ 0/21 0/22 |CAT2| 0/2 ----
> 0/0 |R2|
> 
> You want R1 and R2 to see each other as CDP neighbors.
> 
> CAT1
> ____
> 
> interface 0/1
> switchport access vlan 999
> switchport mode dot1q-tunnel
> l2protocol-tunnel cdp
> no cdp enable
> 
> vlan 10,20,30,40,999
> 
> CAT2
> ____
> 
> interface 0/2
> switchport access vlan 999
> switchport mode dot1q-tunnel
> l2protocol-tunnel cdp
> no cdp enable
> 
> vlan 10,20,30,40,999
> 
> 
> 
> For the trunks 21 and 22 (not running etherchannel)
> 
> I could run all VLANs across both 21 and 22
> I could run VLANS 10,20,30,40 on 21 and 999 on 22
> 
> 
> Are there any issues with either option ? 
> 
> 
> 
> 
> 
> _______________________________________________
> For more information regarding industry leading CCIE Lab training, please
visit www.ipexpert.com

_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Reply via email to