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Openvpn nat and iptables

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Old 11-04-2016
end end is offline
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Openvpn nat and iptables

good day good people


first to tell that firewall and vpn is working as expected, but I notice something strange.

I have host system ip) firewall is blocking everything except port to vpn.
I have vpn on virtualized system (CentOS both host and virtual). They are behind MikroTik router and then to my ISP router. This is a home setup I'm just experimenting.

PREROUTING to all other is blocked by iptables.

I noticed with Wireshark from host that while I'm connected to vpn from another pc that is connecting to ip addresses of websites I visit while in same time is connected to vpn. like: XX.XX.XX public ip tcp udp sites i visit

but is unnecessarily making connections to website ip addresses. She cannot make the reqests because DNS and ports for that are blocked. So this is because postrouting command my best guess. Can this somehow be disabled? First this is a security issue, second its unnecessary.

Someone told me that this is because NAT setup. but I believe that this can be disabled somehow, I didn't find solution yet so maybe someone know how.


Moderator's Comments:
Openvpn nat and iptables We had to correct a lot of spelling errors. Please put more effort into using proper english

Last edited by Scrutinizer; 11-05-2016 at 03:48 AM.. Reason: Spelling
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