REAL WORLD SCENARIO

HI ALL,

I have a real world scenario that I hope you guys can help with... So here we go:

Site A has 2 Nexus 5000 and Site B has 2 Nexus 5000. There is one MetroE that connects SiteA with SiteB. This is all Layer 2 and not Layer 3. I want to take another MetroE from a different provider for Redundancy and connect the two sites.

This customer is huge and 24 Hrs operation.

1) How can I connect the second MetroE without interrupting anything?

2) How can I make the current one primary and if it goes down for the second one to take over?

Remember, all Layer 2 and no Layer 3. I want to do this with little to none interruptions.

thanks for your input.

Comments

  • peetypeety ✭✭✭

    Step 1: please don't post in the CCIE level forums unless you're already at/above the CCNP level.

    Step 2: to answer both questions quickly, I recommend you only connect the second MetroE at site A with 'spanning-tree bpdufilter'.  If the first circuit goes down, unplug it at Site B, and plug in the second circuit at Site B.  Lather, rinse, repeat.

    Step 3: Hire a properly-skilled consultant to properly document and analyze the current spanning-tree topology at both sites, and determine the proper integration plan for this task.  This amount of work is far more than one should expect for free from starving students.

  • Peety,

    Thank you for your comment but let's get something clear.

    1) I think your "Step 1" is uncalled for. I am at a CCNP level and I work for a consulting firm. I have taken charge of this task because I wanted the challege. I don't think it is as easy as you think it is and even at a CCIE level you probably still don't know everything. So to start your response like that is a little selfish and ignorant. This forum is for people who needs help and people who are willing to help people. We ought to be respectful, professional, and courteous toward each other. So, please don't post in the CCIE level forums unless you're already at/above a PROFESSIONAL level.

    2) I posted this scenario with spanning-tree in mind but I wanted more second opinions on it. I don't want to have to physically plug/unplug every time there is a failure. Can it happen automatically? How can I connect the second MetroE without disrupting the network(1st MetroE already in place)? Or have very little impact?

    Looking forward to more responses.

    Thank you.

  • Site A has 2 Nexus 5000 and Site B has 2 Nexus 5000. There is one MetroE that connects SiteA with SiteB. This is all Layer 2 and not Layer 3. I want to take another MetroE from a different provider for Redundancy and connect the two sites.

    This is clearly insufficient information in order to provide a response. What we need to see is a simple diagram detailing the L2 topology including where the spanning tree roots are located for each VLAN.  Also what are the bandwidths of the Metro circuits.

    Any solution provided without the full story would be full assumption and superposition.

    And with this information a solution like you propose would be possible.

    I think what Peety is trying to say - is that you need to present your questions in a better way if you want to have constructive and useful answers.

  • I think what Peety is trying to say - is that you need to present your questions in a better way if you want to have constructive and useful answers.

    Agreed. In a later post there's more information added, talking about scenarios in mind. Well why not post this all up front?

    Just posting a small amount of info on your problem, and expecting a solution, is a bit much. Given that this is a CCIE R&S discussion forum, there's a limit to the amount of free consulting you can expect. That said, there's a lot of clever people here, but they don't have a lot of time.

    What you could instead do is something like this:

    * Give a diagram showing your current layout, and your proposed changes. As much as info as possible. Obfuscate addresses if you must. Remember, we know NOTHING about your network, or your challenges, or restrictions. 

    * Outline your proposed solution(s). 

    * Raise any specific technical issues/questions you may have. 

    You get better responses by saying "Here's what I plan on doing, but I'm concerned about possible impact here and here, and how this will affect recovery times. Does anyone else see any other issues with my proposed design, or perhaps have suggestions on better ways of achieving my desired outcome?"

  • peetypeety ✭✭✭

    1) I think your "Step 1" is uncalled for. I am at a CCNP level and I work for a consulting firm. I have taken charge of this task because I wanted the challege. I don't think it is as easy as you think it is and even at a CCIE level you probably still don't know everything. So to start your response like that is a little selfish and ignorant. This forum is for people who needs help and people who are willing to help people. We ought to be respectful, professional, and courteous toward each other. So, please don't post in the CCIE level forums unless you're already at/above a PROFESSIONAL level.

    This forum is for individuals studying for the CCIE Route/Switch exam.  It's not just a forum for people who need help, nor is it a place where people come just to provide free tech support.  I'm here because I found this forum useful on my journey to CCIE, and because I want to give back to the same community (albeit a "younger generation"), which in my eyes is completely in line with "this forum is for individuals studying for the CCIE Route/Switch exam".

    As far as your level and occupation, let me blunt here: it was not obvious in the least that you're a CCNP or that you're at a consulting firm.  I'd expect a CCNP to be able to articulate the spanning-tree basics of the network when they made the original post, and I'd expect a consultant to be able to provide a summary of the original spanning-tree design concepts used in the network (i.e. root placement and WHY, if VPC is in use and how that factored into the STP design).

    I've seen posts on various forums/lists like this one referring to homework.  Most folks here are doing lots of "homework" to study for the exam, and they'd like others to "explain things another way than the book" in the hopes of providing that light bulb of understanding.  Your original post suggests that you hadn't done any homework.  If you'd come forward with STP basics and design, and showed that you'd made a conceptual attempt at how it'd all come together along with questions about details or risks, you'd get a much stronger response from the community.

    2) I posted this scenario with spanning-tree in mind but I wanted more second opinions on it. I don't want to have to physically plug/unplug every time there is a failure. Can it happen automatically? How can I connect the second MetroE without disrupting the network(1st MetroE already in place)? Or have very little impact?

    Spanning-tree is your answer because it's a layer-2 network.  STP will "block" a port, most likely at/near a point(s) that's logically furthest away from the root bridge, to prevent a loop(s).  The key here is to manage where that block goes, for the most logical traffic flows.  If your N5Ks are doing VPC, that presents a significant "wrinkle" into the STP design, as the VPC peer link "cannot" block on either end due to the rules of VPC.  You also have issues regarding link bandwidth and STP cost; you might be in a scenario where 'spann pathc meth long' is essential for clean simplicity of architecting the path/ring.  Hopefully you're on a modern STP mode, or you're going to want to perform a mode migration as part of this project.

    Consider a lab of four switches, i.e. the CCIE rental racks available from INE.  Use the routers as your PCs/Servers, and the switches as your switches.  You won't be able to simulate VPC on 3550s/3560s, but at least you'll have STP which is essential to the solution.

  • Thank you everyone for posting.

    Peety,

    This time I have to agree with you and everyone else. I could have provided a little bit more details.

    Let me put together details(diagrams/spanning-tree info/vpc) and I'll update.

    Thanks,

Sign In or Register to comment.