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One to One port range forwarding to different port range using IPTABLE?

+1 vote
302 views

After testing and looking at the kernel source, I realize that this mapping:

iptables -t nat -I PREROUTING -p tcp -m tcp --dport 30000:40000 -j DNAT --to [local_ip]:10000-2000

Doesn't do a one-to-one port mapping
e.g.:

100.0.0.1:30000 > 192.168.0.5:10000
100.0.0.1.30001 > 192.168.0.5:10001
100.0.0.1.30002 > 192.168.0.5:10002

I was wondering if it was possible to do the 1:1 port range forwarding to different port ranges or if you have to use individual rules.

posted Aug 5, 2015 by anonymous

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