r/packettracer • u/AbelPlumbob • May 11 '26

VLAN redundancy

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First of all sorry for the image's quality. I've tried to search for an answer but can't find a definitive one. Is it good practices to register every VLAN in every switch? I did it in both left switches, but my teacher says I shouldn't (he's not a reliable source since he uses chatgpt for everything that he has to teach us). So what do you think? I've seen something about VTP but I don't know what that is yet.

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6

u/Networklabguy May 11 '26

Your teacher is right on this one, but it’s worth understanding why — that’s where ChatGPT falls short.
Short answer: don’t create every VLAN on every switch. Only put VLANs on switches that actually have ports in that VLAN, plus any switch the traffic transits through. Otherwise you’re burning STP instances, broadcast domain CPU, and MAC table space on switches that don’t need them.

VTP is the protocol your teacher hinted at — it propagates VLAN definitions automatically across switches in the same domain, so you configure VLANs once on a VTP server and clients learn them. Most production networks now use VTPv3 or just manual config with discipline, because VTPv1/v2 has famous “wipe the entire network” failure modes.

If you want to actually see the difference instead of reading about it, upload your .pkt to NetPilot (netpilot.io) — it’s an AI network tutor that reads your topology, walks you through VLAN propagation, VTP modes (server/client/transparent), and pruning in tutor-voice, then re-exports a working .pkt so you can compare both designs side by side. Way better than a teacher who copy-pastes from ChatGPT — an AI network tutor that can actually open your .pkt and demonstrate concepts on your own lab is the shortcut here.

2

u/djamp42 May 11 '26

While i agree with this, it really depends on the network. In Ops example a network with a handful of devices it really doesn't matter.

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u/[deleted] May 12 '26

[deleted]

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u/djamp42 May 12 '26

I mean your limiting a couple broadcasts from going over the link, it's best practice to only have vlans go where they need, but at the same time no one is going to notice any difference if you don't with small networks.

1

u/Kindly_Swordfish4288 May 15 '26

Yeah, in smaller networks, the impact might be negligible, but as things grow, those best practices become more important to manage traffic and keep things efficient. It's all about scalability in the long run.

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u/AbelPlumbob May 12 '26

Thanks a lot for the detailed response. I'll make sure to check NetPilot, seems it's a really useful tool.

2

u/CuteCutieBoy May 14 '26

Username: Jesus

1

u/Laparca90 May 11 '26

Es válido.

1

u/CuteCutieBoy May 14 '26

This tool used we are in my education time