digraph G {
	graph [layout=dot fontname="Cantarell,sans-serif"];
	node [shape=Mrecord fontname="Cantarell,sans-serif"];
	edge [fontname="Cantarell,sans-serif"];

	subgraph cluster_kernel {
		label = <<font point-size="20">Linux (kernel mode)</font>>;
		color = "brown";
		nft_nat_postrouting   [label="NFTables 規則 (nat, postrouting)"];
	}

	pkt_in  [label="DNS response 封包輸入"];
	pkt_out [label="DNS response 封包輸出"];

	pkt_in                 -> nft_nat_postrouting  [label=<<font color="red"><b>1</b></font>>];
	nft_nat_postrouting    -> pkt_out              [label=<<font color="red"><b>2</b></font>>];
}