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+You may get rst==1 in the following scenes:
+
+##### 1. You didnt run udp2raw with `-a` option, nor did you add the iptables rule needed by udp2raw manually. Then you may get rst==1 from either of the sides.
+
+In this case, you have to run udp2raw with `-a` option, or add iptables-rules manually(maybe with the help of `-g` option)
+
+##### 2. You killed udp2raw client after a connection has already established to server. Then you may get rst==1 from server log.
+
+In this case, its as expected, you can ignore it.
+
+##### 3. You killed udp2raw server while udp2raw client is running. Or you are using udp2raw to connect to an non-existed server. Then you may get rst==1 from client log. 
+
+Start/re-start your server. And ignore the previous rst==1 logs.
+
+##### 4. Not covered by the above scenes, but you still got rst==1
+
+Maybe the NAT middle-box or firewalls is trying to obstruct your connection. You can post a Issue for help. 
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