How does HA2 work ?

L2 Linker

How does HA2 work ?

Hi everyone,


That is the considering architecture :

Two Datacenters, Two 3050 Palo Alto appliances.

There is one switch on each Datacenter and the switchs are connected with a layer 2 optical fiber link

Each appliance is located on each Datacenter and connected to the switch.


Palo Alto ----- Switch -----Layer 2 link------Switch------Palo Alto


I want to setup Active/Standby configuration.

The 3050 PALO ALTO provides dedicated HA ports : HA1 and HA2.


I understand that I have to configure an IP address for each HA1 to allow connectivity between them, so I configure a VLAN for this interconnection (ie :


But I don't find any documentation about the HA2 mecanism and how does it work...

I know that by default, the communication between each HA2 port is based on ETHERNET without any IP address but how the two HA2 ports can initiate communication with the peer if they never talk together before ?


Thanks in advance !

L3 Networker

Re: How does HA2 work ?



look here:


'The HA2 configuration is communicated between devices via the HA1 link.', on the mode "Ethernet" the MAC-Adresse from the HA2-Ports will be exchange over HA1

L7 Applicator

Re: How does HA2 work ?



in ethernet mode, the firewall adds Ethertype 0x7261 to the packets: the passive device simply needs to listen for these packet types

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