Networking noob here. Trying to learn networking with my homelab (virtualized Opnsense) and a friend with experience.
I’m having a conversation with this friend about setting up VLANs and he was saying not to use trunk ports cause they can get congested with too much traffic and slow down the network. Based on what I’ve researched online, it didn’t sound entirely right to me.
I can see where’s he’s coming from if you’re using a trunk port as an uplink to another switch or you’re doing inter VLAN routing, but my case was one gigabit switch with multiple VLANs and using the trunk port to uplink to the gigabit port on the router. From my understanding, you’re pretty much limited by your internet speed at that point.
Not sure if I’m even correct so any help would be appreciated.
My guess he is talking about inter vlan traffic. That’s most commonly where bottlenecks are created. My biggest customer has over 200 vlans and 2 dual amd epic systems as firewall with 32 10gig network connections and aggregation switches in front of some of those to get the throughput. See, you need to use a router to send traffic between vlans and if you want to have granular control over the traffic you can’t just use layer 3 switches with static routes. In your case if you have 1gig from WAN into your firewall and then 1Gig to your switch via vlan trunk every traffic between vlans has to go twice through this 1Gig line instead of a direct connection through the switch. In a Home lab environment I don’t think it would make much difference but in bigger environments it gets trickier with size and vlan count