You can set up two Palo Alto Networks firewalls as an
HA pair; the HA peers should use the same version of PAN-OS and
the same content version. HA allows you to minimize downtime by
making sure that an alternate firewall is available in the event
that the peer firewall fails. The firewalls in an HA pair use dedicated
or in-band HA ports on the firewall to synchronize data—network,
object, and policy configurations—and to maintain state information.
Firewall-specific configuration such as management interface IP
address or administrator profiles, HA specific configuration, log
data, and the Application Command Center (ACC) information is not
shared between peers. For a consolidated application and log view
across the HA pair, you must use Panorama, the Palo Alto Networks
centralized management system.
When a failure occurs on a firewall in an HA pair and the peer
firewall takes over the task of securing traffic, the event is called
The conditions that trigger a failover are:
Palo Alto Networks firewalls support stateful active/passive
or active/active high availability with session and configuration
synchronization with a few exceptions:
The PA-200 firewall supports HA Lite only. HA Lite is
an active/passive deployment that provides configuration synchronization
and some runtime data synchronization such as IPSec security associations.
It does not support any session synchronization (HA2), and therefore
does not offer stateful failover.
The VM-Series firewall in AWS supports active/passive
HA only; if it is deployed with Amazon Elastic Load Balancing (ELB),
it does not support HA (in this case ELB provides the failover capabilities).
The VM-Series firewall in Microsoft Azure does not support