(reposting from Network Infrastructure/LAN, Switching and Routing)
I have an SG300-28PP switch connected to an Aironet 2600 AP. The AP is advertising 5 SSIDs that it maps into 4 separate VLANs, which then connect to a port on the switch configured as a Trunk, with the same VLANs. I have a firewall connected to the switch which is also configured to trunk the same VLANs, so I can advertise multiple networks at the AP and then split / ACL the traffic at the firewall.
I recently tried to add a new network to this setup, configured as VLAN50 on both the AP and the firewall. For some reason though, I am unable to add this new VLAN to either of the trunk ports. Under "VLAN settings" the new VLAN ID is showing as "Disabled" no matter what I do, and as such I can't add it to any of the trunks.
Reading around I saw some mention that you can't enable a new VLAN until the SG300 sees traffic on that VLAN. If that's true, what does that actually mean? I can cause tagged packets to be sent from either the AP or the firewall, and I've even tried creating a VLAN50 access port and connecting a workstation to that - still no dice.
What do I need to do in order to enable my new VLAN and add it to the trunk ports?
