Different IP Domain over OTV ???

[mr_fc]

Hi Expert,

Two data center connected and using  OTV.   Normally we can stretch Vlan domain from one data center using OTV to Other Data Center.

1.    Is there any way that we can stretch Different   Two different IP Domain Vlans over OTV

2.    Can we do QinQ over OTV ?

eg.

Requirement 1 (Different Vlan on both side with different IP Domains)

Vlan 10 (10.1.1.1)--------- Nexus (DC1) ----------OTV------------Nexus(DC2)--------------Vlan20 (20.1.1.1)  ???

Requirement 2 (same vlan on both side but different ip domain)

Vlan 10 (10.1.1.1) --------- Nexus (DC1) ----------OTV------------Nexus(DC2)------------Vlan10 (20.1.1.1)?

any comment would be higly appricated

Regards

[Marwan ALshawi]

Hi there

first of all you need to have a logical approach why yo need to stretch a L2 vlan between two DCs

is it server clustering requriments, is VM requriemnts ..etc

if you are going to have differnt VLAN and differnt L3 IP subnet then there is not need to ass OTV or to use it in this case just use L3 DCI between the two DCs this is for requirements 1

for requirements 2 not sure why you need to keep the vlan same number while the IPs are differnt this dose look a L2 adjacency and as stated above L3 link can dose the job because in any way you need a L3 routing interface to routed between those two differnt IP subents !!

using QinQ is no something you need based on the above, also using QinQ with OTV will be too many encapsulations which is going to make things very complicated,

hope this help

[mr_fc]

Hi Marwan,

Thanks for your reply

Let me rephrase it ,Let say I have two data center 

DC 1 with Vlan 10  SVI 10.0.0.0

DC 2 with Vlan 10  SVI 20.0.0.0

It was never interconnected. Now we have data center interconnected and OTV is running so few vlan are been stretch already eg. 20,30,40 within same subnet

For this old configuration is there any way to stretch using same vlan with different subnet because  changing at DC2 Vlan 10 SVI and its related devices IPs as DC1 would be nightmare

[Marwan ALshawi]

ok, lets put it this way

if you have server in DC1 with ip 10.0.0.1 and another server in DC2 with IP 20.0.0.1 and both in VLAN10

those servers if they need to communicate with each other they need to go to a L3 interface to perform the routing between the two subnets

in other words there is no benefit that i see you can get by extending vlan 10 if its configured with differnt ip subnet

the idea of vlan stretching is to keep L2 adjacency between devices for some servers/hosts requirements

if you dont not need the stretch dont do it

hop this help

[Marwan ALshawi]

dose it make more sense to you now  ?

[Aries Fernandes]

Not sure if this is answered, but here is what I understand...

For case1: You can actually give a shot towards inter-vlan routing via OTV. I see that this was working without much concern. However, I have tested it on only ASR1K routers and not on Nexus.

Here is the link for the configuration if you need for the same:

http://stayinginit.blogspot.in/2013/12/inter-vlan-traffic-over-otv.html

Hope this helps,

I am not sure about case2, so let me do some research on this and get back.

Regards,

Aries