L2 between Data Centers

[Shura182]

Hello guys,

I'm looking for a way to connect two data centers with layer 2 (about 50 VLANs).
I have VPN tunnel between two locations. I have Cisco 6509 in both locations, if it makes sense maybe I can use it for L2 tunneling.
Wondering what method the most reliable to send L2 traffic between two locations.
 

I see there are a few options to extend L2:
VXLAN
GRE Tunnel
L2 Tunneling

If you have such experience, could you please share it? What will be the proffered way?
Unfortunately I don't  way to test it, except the production environment

Thanks!

[icecream-guy]

That depends. what are you needs?   do you want to stretch layer 2 across from DC to DC? seems like you do.
all 3 of the solutions provided have both pros and cons, so it really boils down to what are the project requirements.
your LoE may vary between solutions.  you should have been given a list of goals not just "how do we connect 2 datacenters"
there are many ways to do so.   what are the failover requirements?  are both data centers connected over direct connection
or tunnel runs over Internet?  If internet, are the data centers connected to same ISP? or Different ISP

[deanwebb]

If this is a L2 network for keeping databases in sync, what is the latency between the datacenters?

[Otanx]

I think your problem is going to be support on the 6500s. They don't support VXLAN. I think they can do L2TPv3, but you have to have the right supervisor cards, and need the expensive licenses for it. I have not heard of using GRE for L2 so not sure how that works. There is also OTV, but that is on Nexus only.

-Otanx

[Shura182]

I'm looking to migrate all VMs from one DC to another one. This will be temporary solution. I have redundancy on the Internet, but I will need to have for the all L2 link.

Both DCs connected to the Internet, to the same ISP.
The idea to have L2 over Internet (VPN). If I can use 6509 for L2 it will be great, if not, probably I will need to have some devices for GRE/L2TPv3/VXLAN.

Just wondering what will be the easiest way to set up L2, to send multi VLANs across L2?
Any preference to use on of these methods GRE/L2TPv3/VXLAN?

[Otanx]

If it is a temporary solution (and will really be temporary) I would use whatever the hardware I had that could do. If I didn't have anything then L2TPv3 can be done in Linux. Just spin up a box on either side with a couple interfaces. One interface for the L2TP tunnel source/end point, and one interface to accept a trunk port from the network to send over the tunnel.

If it going to be a permanent solution I would go with VXLAN, and setup everything as leaf/spine. Even if I had to procure, and put in extra effort to do so.

-Otanx

[Shura182]

If it is a temporary solution (and will really be temporary) I would use whatever the hardware I had that could do. If I didn't have anything then L2TPv3 can be done in Linux. Just spin up a box on either side with a couple interfaces. One interface for the L2TP tunnel source/end point, and one interface to accept a trunk port from the network to send over the tunnel.

If it going to be a permanent solution I would go with VXLAN, and setup everything as leaf/spine. Even if I had to procure, and put in extra effort to do so.

-Otanx

Thank you Otanx!