What exactly is "VLAN Interface" enable/disable for switches doing? Something re: Protocol VLANs?

What exactly is "VLAN Interface" enable/disable for switches doing? Something re: Protocol VLANs?

What exactly is "VLAN Interface" enable/disable for switches doing? Something re: Protocol VLANs?
What exactly is "VLAN Interface" enable/disable for switches doing? Something re: Protocol VLANs?
2023-11-15 03:09:42

This is just a minor clarification question. I've been experimenting with switching over a few clients from UniFi to Omada. Routing and general network services is handled by OPNsense. None of the sites are big, less then 20 switches+waps, 20-70 VLANs, less than 400 clients max at any given time. Overall it's been reasonably pleasant and smooth, but one curiosity I've come across in the Omada GUI is in the switch config where it won't allow "enabling" more then 16 VLANs. In terms of switch VLAN support, a minimum of 64 is the lowest I've seen in a long time and most (including UI switches) support 256 or more, and the TP-Link Jetstream switches indeed specify 4096 max vlan groups.

 

So that's left me confused about where the 16 is coming from and what that setting is even for. Even if a given VLAN isn't "enabled", if I set the port profile to tag it everything on the face of it seems normal, the connected device is on the right VLAN, and I can make port profiles that include >16 VLANs as tagged networks and apply them. Which is all as expected. But after playing with a few switches standalone I know 16 protocol VLANs is the max, even though it looks like that isn't exposed (yet?) in Omada vs the switch native GUI/CLI. Is the config somehow related to that and can just be ignored for normal traffic with WAPs/switches handling up to 4k networks?

 

Thanks so much for any clarification there!

 

  0      
  0      
#1
Options
2 Reply
Re:What exactly is "VLAN Interface" enable/disable for switches doing? Something re: Protocol VLANs?
2023-11-18 01:44:10

So just a reply to myself in case anyone else ever sees this and has the same question: while I haven't analyzed traffic patterns yet I think the feature has something to do with protocol or L3, because even turning all of them off has no effect on the network. So not something to be concerned about when deploying Omada if you're coming from another platform.

  0  
  0  
#2
Options
Re:What exactly is "VLAN Interface" enable/disable for switches doing? Something re: Protocol VLANs?
2023-11-18 23:00:55

  @sonaric 

 

A VLAN interface is basically a routed interface (gateway) for a particular VLAN. On a L3 switch, it can be usually created only after routing is enabled on it. A VLAN interface is not directly related to "protocol VLANs" which is a VLAN assignment method.

 

4096 is the maximum number of simultaneous VLANs allowed on a switch.

 

There are several VLAN assignment methods. In most cases, a PVID (1 - 4096), is used to assign a VLAN. However, a VLAN can be also assigned based on a MAC address, protocol or even subnet and that’s where further limitations exist. That’s because VLANs are put into groups in those assignments and there must be a limit on the number of items in a group. Those limitations can be found in the spec for a particular switch.

 

I’m not sure what the limit of 16 VLANs you see, but the Omada and other products of this kind will certainly limit the number of items in their own groups, introducing that way additional limitations.

Kris K
  0  
  0  
#3
Options

Information

Helpful: 0

Views: 406

Replies: 2

Related Articles