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howto.md

+# How to
+
+## port forward
+
+iptables:
+
+```
+echo 1 > /proc/sys/net/ipv4/ip_forward
+iptables -t nat -A PREROUTING -p tcp --dport 11191 -j DNAT --to-destination 1.1.1.1:1111
+iptables -A FORWARD -p tcp -d 1.1.1.1 --dport 1111 -j ACCEPT
+iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
+```
+
+socat:
+
+```
+socat tcp-listen:444,fork,reuseaddr tcp:microsoft.com:443
+```
+