diff --git a/setup/system.sh b/setup/system.sh
index ed399ba0..1e1045ff 100755
--- a/setup/system.sh
+++ b/setup/system.sh
@@ -356,6 +356,7 @@ systemctl restart systemd-resolved
 rm -f /etc/fail2ban/jail.local # we used to use this file but don't anymore
 rm -f /etc/fail2ban/jail.d/defaults-debian.conf # removes default config so we can manage all of fail2ban rules in one config
 cat conf/fail2ban/jails.conf \
+    | sed "s/PUBLIC_IPV6/$PUBLIC_IPV6/g" \
 	| sed "s/PUBLIC_IP/$PUBLIC_IP/g" \
 	| sed "s#STORAGE_ROOT#$STORAGE_ROOT#" \
 	> /etc/fail2ban/jail.d/mailinabox.conf