Hello Dan ,
Its simple , Just create a source NAT rule with following term :
source {
rule-set test {
from zone XXXX;
to zone YYYYt;
rule Slough_LAN-to-Untrust-SNAT {
match {
source-address 10.1.0.0/16;
destination-address 10.2.0.0/16;
}
then {
source-nat {
off ;
}
}
}
}
And make this rule on top of the existing NAT rule so that It will be preferred . ( Keep in mind that the NAT rule are traverses as per the order ) .