OpenVPN Server Topology Choices

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Joined: Fri Nov 09, 2018 6:01 am

OpenVPN Server Topology Choices

Post by fengou » Fri Nov 09, 2018 6:12 am

From the
These are available options as values to the --topology parameter in --dev tun mode. Each topology is described further in its own section below.

The recommended topology for modern servers. Note that this is not the current default. Addressing is done by IP & netmask.
This is the old topology for support with Windows clients running 2.0.9 or older clients. This is the default as of OpenVPN 2.3, but not recommended for current use. Each client is allocated a virtual /30, taking 4 IPs per client, plus 4 for the server.
This topology uses Point-to-Point networking. This is not compatible with Windows clients, though use with non-Windows allows use of the entire subnet (no "lost" IPs.)

By default, the SE server using "net30" topology, so question is how I can change the topology to "subnet", or could you please help where to modify from the source code?

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Joined: Mon Feb 24, 2014 11:03 am

Re: OpenVPN Server Topology Choices

Post by thisjun » Thu Nov 22, 2018 7:44 am

Tun mode OpenVPN of SoftEther VPN uses PPP module for L2TP.
If you want to modify the source code about it, please check IPC.c. ... edar/IPC.c

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