NAT Active/Active HA Binding Tab
Policies > NAT > Active/Active
HA Binding
The Active/Active HA Binding tab is available only if the firewall
is in a high availability (HA) active/active configuration. In this
configuration, you must bind each source NAT rule (whether static
or dynamic NAT) to Device ID 0 or Device ID 1; you must bind each
destination NAT rule to either Device ID
0
,
Device ID
1
,
both
(Device
ID 0 and Device ID 1), or to the active-
primary
firewall.
Select an
Active/Active HA Binding
setting
to bind the NAT rule to an HA firewall as follows:
0
—Binds the NAT rule to the firewall
that has HA Device ID 0.
1
—Binds the NAT rule to the firewall
that has HA Device ID 1.
both
—Binds the NAT rule to both the
firewall that has HA Device ID 0 and the firewall that has HA Device
ID 1. This setting does not support Dynamic IP or Dynamic IP and
Port NAT.
primary
—Binds the NAT rule to the
firewall that is in HA active-primary state. This setting does not
support Dynamic IP or Dynamic IP and Port NAT.
You typically configure device-specific NAT rules when the two
HA peers have unique NAT IP address pools.
When the firewall creates a new session, the HA binding determines
which NAT rules the session can match. The binding must include
the session owner for the rule to match. The session setup firewall performs
the NAT rule matching but the session is compared to NAT rules that
are bound to the session owner and translated according to one of
the rules. For device-specific rules, the firewall skips all NAT rules
that are not bound to the session owner. For example, suppose the
firewall with Device ID 1 is the session owner and the session setup
firewall. When Device ID 1 attempts to match a session to a NAT rule,
it ignores all rules bound to Device ID 0.
If one peer fails, the second peer continues to process traffic
for the synchronized sessions from the failed peer, including NAT
translations. Palo Alto Networks recommends you create a duplicate
NAT rule that is bound to the second Device ID. Therefore, there
are two NAT rules with the same source translation addresses and
the same destination translation addresses—one rule bound to each
Device ID. This configuration allows the HA peer to perform new
session setup tasks and perform NAT rule matching for NAT rules
that are bound to its Device ID. Without a duplicate NAT rule, the
functioning peer will try to perform the NAT policy match but the
session won’t match the firewall’s own device-specific rules and
the firewall skips all other NAT rules that are not bound to its
Device ID.