Multiple L2TP-IPsec clients behind same NAT.

[Oooo1]

Do SoftEther support multiple L2TP/IPsec clients behind the same NAT configuration ?
That is some different clients with different Win OSes is behind one NAT with one external IP and is it possible multiple connections from such clients when only one IP - NAT external IP will be as IP of incoming connection.

[dnobori]

Unfortunately, that is impossible by the design of IPsec protocol.

When using IPsec, the server port is fixed to UDP 500/4500. This cannot be changed.

Therefore, the NAT cannot switch the client's requests to multiple appropriate VPN servers behind the NAT.

[Oooo1]

Limitation of L2TP or IPSec ?
Look at this: http://wiki.strongswan.org/issues/365

[Oooo1]

It sound strange, but I have been able to establish connections from 2 cleints: Win XP and Win 7 sited behind one external IP NAT.
And the cliens has been got different IPs fron specified in SecureNAT dhcp pool.

[dnobori]

I mean that you cannot setup and run two different L2TP/IPsec servers behind a single NAT.

[Oooo1]

Ohh, no.
I need to connect 2+ clients sited behind the same nat on some subnet but on the same subnet (for both or more clients) to 1 the same l2tp/ipsec server sited on other net behind its nat also.
But 2 clients will have the same external source IP - their nat IP.
Do SoftEther support such mode ?

[thisjun]

What error is occurring in such environment?