We introduce carp-master.sh, to be executed on fw1:

#!/bin/ksh


sysctl net.inet.carp.preempt=1

#Outside
cat <<EOF > /etc/hostname.vr1 
dhcp
EOF

#Inside
cat <<EOF > /etc/hostname.vr2
inet 10.0.112.252 255.255.255.0 NONE
EOF


#Outside carp
cat <<EOF > /etc/hostname.carp0
10.0.12.251 vhid 1
EOF

#Inside carp
cat <<EOF > /etc/hostname.carp1
10.0.112.251 vhid 1
EOF


# PfSync Interconnect
cat <<EOF > /etc/hostname.vr3
inet 10.0.227.252 255.255.255.0 NONE
EOF

#PfSync
cat <<EOF > /etc/hostname.pfsync0
syncdev vr3
EOF

chmod 640 /etc/hostname.*

ifconfig pfsync0 down
ifconfig pfsync0 up

sh /etc/netstart
      

... and carp-slave.sh, to be executed on fw2:

#!/bin/ksh


sysctl net.inet.carp.preempt=1

#Outside
cat <<EOF > /etc/hostname.vr1 
dhcp
EOF

#Inside
cat <<EOF > /etc/hostname.vr2
inet 10.0.112.253 255.255.255.0 NONE
EOF



#Outside carp
cat <<EOF > /etc/hostname.carp0
10.0.12.251 vhid 1 advskew 100
EOF

#Inside carp
cat <<EOF > /etc/hostname.carp1
10.0.112.251 vhid 1 advskew 100
EOF


# PfSync Interconnect
cat <<EOF > /etc/hostname.vr3
inet 10.0.227.253 255.255.255.0 NONE
EOF

#PfSync
cat <<EOF > /etc/hostname.pfsync0
syncdev vr3
EOF

chmod 640 /etc/hostname.*

ifconfig pfsync0 down
ifconfig pfsync0 up

sh /etc/netstart