VyOs - Open source router and firewall platform


Building an open source network OS for the people, together.


Take a third option: site to site OpenVPN

I've written a long series of post about setting up IPsec VPNs between NATed machines. As you've already seen, with some creative configuration it's possible, but is it always ...
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Interaction between IPsec and NAT (on the same router)

I've just completed a certain unusual setup that involved NATing packets before they are sent to an IPsec tunnel, so I thought I'll write about this topic. Even in perfectly ...
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Setting up GRE/IPsec behind NAT

In the previous posts of this series we've discussed setting up "plain" IPsec tunnels from behind NAT. The transparency of the plain IPsec, however, is more often a curse than a ...
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How to setup an IPsec connection between two NATed peers: using id's and RSA keys

In the previous post from this series, we've discussed setting up an IPsec tunnel from a NATed router to a non-NATed one. The key point is that in the presence of NAT, the ...
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Why IPsec behind 1:1 NAT is so problematic and what you can do about it

Not so long ago the only scenario when the issues with IPsec and NAT could arise was a remote access setup, while routers invariably had real public addresses and router to ...
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