Correct IP setting when two firewalls connected to one ISP.

L4 Transporter

It's easy to get confused by Palo Alto's various uses of VLAN.


A "VLAN" interface is different from a "Layer 3" interface that has 802.1q vlan tags enabled.


On a PA device "VLAN" interfaces are used to create a virtual switch using ports on the firewall, and allow them to operate as layer 2 interfaces without routing abilities.  Essentially, it create a bridged interface using all the VLAN interfaces.


If you want to enabled tagged (or untagged) 802.1q vlans on interfaces, then configure them as "Layer 3" and create sub-interfaces with the vlan tag set there.


Would be nice if PA updated their UI to remove the ambiguous and confusing "VLAN" interface type.  "Bridge" would be more accurate.

Tags (1)
L4 Transporter

I couldn't agree with you more.  This really confused me the first time I used PAN and the documentation explaining this wasn't great.

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