VLAN routing issues - New to Packet Tracer and need help please!

[ceceliaaa]

Hey guys,

I am super new to packet tracer and I have been tasked with creating a small network for my end of year project at school. I have 2 routers, 2 switches, and 3 end-devices. My network has 3 VLANs and I have been working away at this for about a week now and I just can't figure out what I am doing wrong. The devices connected to my second router can't communicate with the devices connected to router1. I have gone over it a few times and asked my colleagues for help and no one can find a fix. Any help would be greatly appreciated! I've attached my packet tracer file if any kind soul out there could take a look for me and give me some tips to get connectivity throughout my network!

Edit: my passwords for my Switches and Routers are the same with the console password being ciscoconpass and the enable password being ciscoenpass

[Joseph W. Doherty]

Ah, you did good posting your PT file too.

Better, would be not having device passwords or posting what those are.

[ceceliaaa]

oh right I totally forgot! my passwords are the same for all devices, the console password being ciscoconpass and the enable password being ciscoenpass

[Jens Albrecht]

There are a few things to note.

First of all, the major issue is a design error because you try to use the same IP subnet for Vlan 99 on both sides and this will never work! You must use different subnets because in case of connected networks the router will never send any traffic for these networks to its neighbors.

Then R2 does not have any IP address on its interface Gi0/0/1 or subinterfaces with an IP address. As explained above this network must be different from the one that R1 uses on its interface Gi0/0/1.99. This also means that S2 and PC-C need IP addresses in the new network.

Finally, you only configured static routes on R2 but there are no static routes at R1. So R1 needs such a route for the network that you assign to R2 on its internal interface (and S2 and PC-C).

Your configs seem to be the result of trying and testing various things so there might be some other minor issues as well.
Nevertheless, taking care of the 3 major issues mentioned above should set you on the right path and get you going.

HTH!

[Joseph W. Doherty]

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@Jens Albrecht wrote:

First of all, the major issue is a design error because you try to use the same IP subnet for Vlan 99 on both sides and this will never work! You must use different subnets because in case of connected networks the router will never send any traffic for these networks to its neighbors.

Actually, there are ways to span L2 and a subnet across L3, but unlikely this is expected on your Capstone project.  I only mention it, because, technically, it can be done, so "never work" isn't 100% correct.  Yet, for this case, pretend it's true.

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@Jens Albrecht wrote:

Finally, you only configured static routes on R2 but there are no static routes at R1. So R1 needs such a route for the network that you assign to R2 on its internal interface (and S2 and PC-C).

Also want to mention, the real key to understanding about routing, a router "knows" about its directly connected networks, if it has an interface in them, but networks not directly connected to the router, such as on the far side of even a directly connected router, somehow, need to be make known to the router, and also, next hop to send packet to, to get them on the way to a distant network.

"Somehow" can be accomplished by static routes, and/or, can be accomplished by a dynamic routing protocol.  The former doesn't scale very well, although summary routes, can in some cases, greatly reduce the number of static route statements needed.  For this topology, static route statements should be fine.

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@Jens Albrecht wrote:

. . . there might be some other minor issues as well.

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I haven't verified all what @Jens Albrecht also noted, although I presume he's correct, but also, without much review, noticed you have a VLAN 30 on switch1, and a subinterface for it on router1, but you don't allow it on the switch1 trunk.

Like Jens, I wouldn't declare there are no other issues, if fact, I believe there are.

What can help in project like this, is a sheet of paper, where you can write down device IP, VLAN, etc. assignments, so you can compare what you're doing, side-by-side, easily, in one place.

Oh, and in a real wired network, you probably wouldn't be using an IPv4 /21 for hosts.  (Do you know why?)  Also, you might use an IPv4 /31 for a p2p.

[Jens Albrecht]

@Joseph W. Doherty wrote:

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Actually, there are ways to span L2 and a subnet across L3, but unlikely this is expected on your Capstone project.  I only mention it, because, technically, it can be done, so "never work" isn't 100% correct.  Yet, for this case, pretend it's true.

Of course I know how to use techniques like L2VPNs to bridge such networks but what's the point to mention such tools when talking to beginners? This leads to nothing but confusion.

With your kind of thinking Wendell Odom would be forced to rewrite all of his CCNA-level books.
Definitely a bad idea...

[Joseph W. Doherty]

With your kind of thinking Wendell Odom would be forced to rewrite all of his CCNA-level books.

Really?  I don't recall his books providing incorrect information.  There's a difference between not mentioning something and describing something that's incorrect.

Of course I know how to use techniques like L2VPNs to bridge such networks but what's the point to mention such tools when talking to beginners? This leads to nothing but confusion.

Don't recall saying you didn't know yourself.  But, as you admit you know this can be done confirms it can "never work" isn't 100% correct, right?

Yes, I agree this capability shouldn't have been mentioned, but, by poor wording, you stated it cannot be done.  The confusion, I think, may come later when OP finds out it can be done, and then wonders what other information he obtained might also be incorrect.

Consider, how you would feel about Wendell's book if he said something can "never work", but you later discover it can.

[Jens Albrecht]

The CCNA world uses a bunch of simplifications and has clear boundaries of what you can or cannot do due to the very limited toolset you have available at that point. This really helps students to focus on getting a solid understanding of the basics before moving on and enhancing their toolset step-by-step later on.

My answer to the same question can be very different depending on the context and the person asking because I always try to adjust my explanations to the knowledge and toolset that this person appears to have.

In this case it is obvious that he is just doing his very first steps into the networking world so that - based on the CCNA toolset - trying to use the same network on both sides will never work.

For the same reasons I focused on the 3 problems preventing connectivity between both sides. I noticed several minor issues but did not mention them as they have nothing to do with the connectivity problem.

[Joseph W. Doherty]

Alas, we're "not on the same page".

If you're arguing that depending where you're in learning a subject, it's beneficial to limit information presented, I completely agree!

If you're also arguing that limiting information is also done by providing incorrect information, I disagree.

If your original reply limited itself to here's what should or ought to be done, or commonly/typically done, or even good/best practice, I wouldn't have written my reply to yours.

But as you recommended/suggested was the only way to do it, yet that's incorrect, I didn't want to leave such an impression.  So, I only mentioned it's not 100% correct, and there are ways to span L2 across L3, but I didn't recommend doing such (or go into the gory details), wrote it unlikely such and approach would be expected, an even wrote what you wrote let's pretend it's completely true.

My purpose was, again, to make it known there is another possible way, but go with what you suggested, i.e. in this case, pretend it's the only way.

My suspicion is, by ". . . try to use the same IP subnet for Vlan 99 on both sides and this will never work!" was meant to emphasize, what OP was doing will never work, as it is.  In just that, I agree, but in a broader context, again, it might be done.

BTW, in a case like Wendell's books, often there are proof reader, editors, and/or readers of the material, to try to insure material is accurate and avoid any misinterpretation before book is published.  (Even with all that, technical books may have an on-line source for corrections.)

Personally, I welcome questions about anything I post.  Usually, I poorly explained something, or made a legitimate error but sometimes it's a matter of opinion, which may end with I convince the other party to my viewpoint, sometimes they convince me to their viewpoint, and sometimes we just end up "respectfully disagreeing".

[Jens Albrecht]

I tried to explain that I wrote my answer having the limited toolset of a CCNA-level student in mind. I will never intentionally provide incorrect information as this would be just plain stupid. Maybe my wording does not 100% match what I want to express as I am not a native speaker. Anyway, this discussion is going in circles and leads to nowhere. So I simply agree to respectfully disagree.

[Joseph W. Doherty]

. . . as I am not a native speaker.

Ah, well, that could explain a whole lot!!!

Firstly, you're English composition is good enough it's not obvious, at least to me, you're not a native English speaker.

Second, I complement you on the additional effort it takes to compose in a foreign language, especially English, as it's such a broad language with so many rules and exceptions to those rules.

As to "going in circles", very possibly, as it's actually unclear, to me, what we disagree on.

Your initial reply to my initial reply to yours, took, it seems, great exception to what I wrote, and honestly, I've been wondering why such a strong reaction.  Likewise, my follow on replies, tried to clarify my intent and concerns, but seemed to be almost totally ignored, although, perhaps now, better said might be not fully understood.  (Then, I don't consider myself a good writer, either.)

Anyway, I agree we disagree on something, although, again, unsure at this point, exactly what.  So, we'll leave it there.

[Joseph W. Doherty]

@ceceliaaa haven't forgotten about you.

Have you had any more success getting your project network to work?

If not, don't be shy about posting follow up questions.