I am trying to isolate all the ports on a particular card on a 4000M. Connected to these ports are an external hub on another floor and two firewall. I've created a vlan number 10 named "Outside" and tagged configured the switch to tag all 3 of those ports. If I specifically change the default vlan to "No", then the devices on the same vlan cannot communicate. I'm confused. What am I doing wrong here?