0

We're planning a new networking for the new office and, since I want to manage the three floor with 3 different VLAN Im planning to handle it with a layer 2 switch ( I looked for the cisco 200 series) . My question is if this layer 2 switches of cisco supports the VLAN who is gonna handle the ip addresses? Do I have to use a router wired to each VLAN interfaces and use the same net address as I set on VLAN net address? In this case do you think it's better use a layer 2 switch with routers or a layer 3 switch (that should handle IP protocol) without routers? Hope I've been clear. Thanks

0wn3r
  • 866
  • 1
  • 8
  • 21
  • 1. Do you have specific needs or requirements for implementing these VLAN's other than just "I want to manage the three floor with 3 different VLAN", which seems like a fairly vague reason to me. 2. If you use layer 2 switches then you will need a router to route traffic between the VLAN's. If you use layer 3 switches then they can be configured to perform the routing for traffic between the VLAN's. – joeqwerty Feb 07 '13 at 15:28
  • 1.My main goal is to have three separate lan, but in case I want to manage route between them. 2. so do I need only a router 'before' the switch. correct? 3.If I use a layer 3 switch I need a router in order to manage the wan connection, so I need a router in any case? – 0wn3r Feb 07 '13 at 15:32
  • 1. You haven't stated why your goal is to have 3 seperate LAN segments. What is the underlying reason for having 3 LAN segments? Do you have technical or legal reasons? Don't introduce unneccessary complexity if you don't have clearly defined needs and requirements. 2. Yes, you need a router in either case because you need internet access. – joeqwerty Feb 07 '13 at 15:38
  • The reason because I want 3 different LAN is because I want better performance on each network, reducing broadcasting and so on...and the reason I don't want to use subnetting is because it depends on the client settings and I don't have full control on the clients machine, and I need different Qos on each LAN. – 0wn3r Feb 07 '13 at 15:43
  • Do you know that you have a performance problem *currently* with broadcast traffic? What have you done to confirm this diagnosis? Also, it sounds like you don't understand that implementing VLANs also means implementing multiple subnets. You *will* be reconfiguring the endpoint devices to do this, full stop. – mfinni Feb 07 '13 at 15:50
  • 1
    Implementing something based on a vague idea that things aren't working correctly but having no supporting evidence + Not having access or control over all of the components that would be affected by this implementation = a recipe for a big fat clusterf#@ck. – joeqwerty Feb 07 '13 at 15:54
  • I'm young and unexperienced, plus I do this work from less than a year and it sounds like David Schwartz with 3 lines of answer helped me out much more than your rudes comments, you will be FOR SURE more experienced and have better knowledge than me but F#@ck I thought this was an helps stack, and I don't think my request is vague. Just vote down the answer if you think it sucks. Thanks for help. – 0wn3r Feb 07 '13 at 16:03
  • 1
    I wasn't being rude. I was being practical and reasonable. Not having clearly defined needs, requirements, goals and objectives for implementing something is a recipe for problems. You said that you want to implement some VLAN's and I asked you why you want to implement them. It's a perfectly reasonable question on my part. If an employee went around implementing things without a clear understanding of WHY they needed to be implemented and without a clear objective FOR implementing them they wouldn't last very long in their job or in this profession. – joeqwerty Feb 07 '13 at 16:21
  • And don't be so sensitive. You're going to get "pushback" in your IT career, whether it's on this site or from your boss or from your boss's boss. Learn to deal with it and defend your position. You need to implement some VLAN's? OK, defend that position so that we can give you practical, reasonable answers that help you achieve your goals. Are you going to pout every time someone pushes back? You'd better get used to it because that's the way of the world. I have to justifiy everything I do, because a business isn't in business to be my personal playground. – joeqwerty Feb 07 '13 at 16:23

1 Answers1

4

You can do it either way. You can use an L3 switch with a routing interface in each VLAN or you can use a router with an IP address in each VLAN. L3 switches are often more convenient because it makes it easy for your routing architecture to track your bridging architecture.

David Schwartz
  • 31,449
  • 2
  • 55
  • 84
  • so do you suggest a L3 switch with a 'routing interface' in each VLAN (this routing interface is just logical right?) – 0wn3r Feb 07 '13 at 15:37
  • 2
    Yes, each VLAN needs its own SVI. Yes, the SVI is logical. – joeqwerty Feb 07 '13 at 16:32
  • thanks joeqwerty, I didn't answer to your lasts comments but I understand your point of view and I respect it. I think I'm still bit confused about VLANs to open a discussion with you about it. I hope you will help me out with my future questions. Thanks again – 0wn3r Feb 07 '13 at 16:52
  • I'm glad to help when I can and I meant no offense by any of my comments. Tactfulness isn't my strong point but I'm glad that having a forgiving nature is yours. :) – joeqwerty Feb 07 '13 at 16:58