[kva.kva]

1'st check Tracker for number of NAT rule which is apllied.

NAT rules are checked one after another, like usual rules in Rule Base.
Bidirectional NAT applies only to automatic NAT rules

Good quote
"The detailed logic of Bidirectional NAT is as follows:
• If the first match on a connection is on a Manual NAT rule, no further checking
of NAT Rule Base is done.
• If the first match on a connection is on an Automatic NAT rule, then the rest of
the NAT Rule Base is checked, one rule at a time, to see if another Automatic
NAT Rule matches the connection. If it does, both rules are matched, and no
further checking is performed.

The operation of Bidirectional NAT can be tracked using the SmartView Tracker,
using the fields NAT Rule Number and NAT Additional Rule Number. The
“additional rule” is the rule that matches the automatic translation performed on
the second object in Bidirectional NAT."