diff --git a/netflow/iptables.sh b/netflow/iptables.sh
index de462ed..1abed5e 100644
--- a/netflow/iptables.sh
+++ b/netflow/iptables.sh
@@ -8,10 +8,10 @@ __main() {
 	update-alternatives --set iptables /usr/sbin/iptables-legacy 2>/dev/null
 	update-alternatives --set ip6tables /usr/sbin/ip6tables-legacy 2>/dev/null
 
-	_owner_ids=$(ps -eo gid --no-headers | sort -u)
+	readarray -t _owner_ids < <(3003 51000)
 	_chain="output_netflow_owner_51000"
 
-	for _owner_id in $_owner_ids; do
+	for _owner_id in "${_owner_ids[@]}"; do
 		for cmd in iptables ip6tables; do
 			$cmd -t mangle -N "$_chain" 2>/dev/null || true