two servers in different location but on same subnet

[julxu]

Hi

I have forgot this technology name, but, I remember it can achive on between Nexus 7000s in two location, and also between two catalyst 6500.

Can I ask if it can be done between one nexus and one catalyst 6500?    they are on different location?

Any comment will be appreciated

Thanks in advance

julxu              

[Reza Sharifi · Accepted solution]

Hi,

Not clear exactly what you are asking, but if you are talking about a layer-2 trunk between a 7000 and a 6500, yes, it can be done.

Or are you referring to VSS or vPC?

HTH

[rsimoni · Accepted solution]

if you are refferring to VSS and vPC, as Reza is suggesting, yes the 2 cat6k or N7k can be in different locations.

However having MC-LAG (or aka Multichassis Ethern Channel) spanning across 2 remote locations might represent an issue in terms of cabling.

Or maybe you were referring to OTV which is a way to extends Layer 2 LANs over any network that supports IP which also lets you achieve your goal. But this is available on Nexus 7000 only not on Cat6k.

Riccardo

[julxu]

yes, it is OTV, the layer2 over two data centre. I thought I had heared on cisco networker conference about two years, there is a commets that the two Cat6500s can do the same thing. just different commands.

just want confirm if it is possible?

[Steve Fuller · Accepted solution]

Hi,

The Catalyst 6500 hardware in the form of the Sup 2T is OTV capable, but the feature is not yet supported within IOS on the platform.

Regards

Sent from Cisco Technical Support iPhone App

[julxu]

Thanks steve.

one more question, except OTV, both VSS and vPC can not use to expend vlan between two data center in long distance case?

Please confirm

Julie

[Reza Sharifi · Accepted solution]

Yes, you can. Each switch in the case VSS or vPC can be in 2 different physical locations.  As long there is fiber to support the distance, you are good to go

HTH

[julxu]

that is a great news, thanks for advice. so, VSS and vPC which one is better  two data center in two geographical location?

[Steve Fuller · Accepted solution]

As in many cases, I think which one is better really depends upon your situation.

For extending Layer-2 between data centre you can use VSS, vPC or OTV and the functionality they provide is very similar. The choice could be made based upon the hardware you already have. For example if you already have Catalyst 6500 and are running VSS within a data centre, then VSS would be the obvious choice as there would be limited additional spend and you already have experience supporting the feature. On the other hand if you have Nexus 7000 and are running vPC, then vPC or OTV would probably be the better choice.

There are quite a number of design documents that would be worth you reviewing.  One place to start would be the Cisco Data Centre Interconnect section of the Data Centre Solutions section of CCO. The Data Centre Interconnect At A Glance will give you a quick overview of what each solution offers, the platforms supporting the feature etc.

Other documents that you should consider reviewing:

- Cisco Data Center Interconnect Design and Implementation Guide Phase 1 - Ethernet-based Solution goes into the considerations for building interconnects using both VSS and vPC

- Cisco Overlay Transport Virtualization Technology Introduction and Deployment Considerations Whitepaper talks in detail about the operation and deployment of OTV on the Nexus 7000.

If you're going to use one of these features to extend Layer-2 between data centre, I would definitely recommend you read some or all of the above. In my opinion extending your broadcast domain across two sites like this is not something to be taken without very careful consideration in design and deployment.

Regards