Trouble: Communication between Server and Android.

[NiloRamirez]

Hi, how are you?
I'm here because i'm with some troubles. I'm trying to configure a SoftEther Server with an Android tablet.
The communication between the Server and an Windows Client is working, but with my tablet it doesn't work.
I saw at the "server_log" folder and found this log:

2016-02-22 17:49:45.295 IPsec Client 2 (192.168.0.106:500 -> 192.168.0.201:500): A new IPsec client is created.
2016-02-22 17:49:45.296 IPsec IKE Session (IKE SA) 2 (Client: 2) (192.168.0.106:500 -> 192.168.0.201:500): A new IKE SA (Main Mode) is created. Initiator Cookie: 0x92322E8D27DBA64A, Responder Cookie: 0xB0CB5300BDF07886, DH Group: MODP 1024 (Group 2), Hash Algorithm: SHA-1, Cipher Algorithm: AES-CBC, Cipher Key Size: 256 bits, Lifetime: 4294967295 Kbytes or 28800 seconds
2016-02-22 17:49:45.508 IPsec Client 2 (192.168.0.106:4500 -> 192.168.0.201:4500): The port number information of this client is updated.
2016-02-22 17:49:45.509 IPsec Client 2 (192.168.0.106:4500 -> 192.168.0.201:4500):
2016-02-22 17:49:45.509 IPsec IKE Session (IKE SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): This IKE SA is established between the server and the client.
2016-02-22 17:49:46.295 IPsec IKE Session (IKE SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): The client initiates a QuickMode negotiation.
2016-02-22 17:49:46.296 IPsec ESP Session (IPsec SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): A new IPsec SA (Direction: Client -> Server) is created. SPI: 0x5A676B03, DH Group: (null), Hash Algorithm: SHA-1, Cipher Algorithm: AES-CBC, Cipher Key Size: 256 bits, Lifetime: 4294967295 Kbytes or 28800 seconds
2016-02-22 17:49:46.297 IPsec ESP Session (IPsec SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): A new IPsec SA (Direction: Server -> Client) is created. SPI: 0x686BF5F, DH Group: (null), Hash Algorithm: SHA-1, Cipher Algorithm: AES-CBC, Cipher Key Size: 256 bits, Lifetime: 4294967295 Kbytes or 28800 seconds
2016-02-22 17:49:46.302 IPsec ESP Session (IPsec SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): This IPsec SA is established between the server and the client.
2016-02-22 17:49:47.286 IPsec Client 2 (192.168.0.106:4500 -> 192.168.0.201:4500): The L2TP Server Module is started.
2016-02-22 17:49:47.325 L2TP PPP Session [192.168.0.106:1701]: A new PPP session (Upper protocol: L2TP) is started. IP Address of PPP Client: 192.168.0.106 (Hostname: "anonymous"), Port Number of PPP Client: 1701, IP Address of PPP Server: 192.168.0.201, Port Number of PPP Server: 1701, Client Software Name: "L2TP VPN Client", IPv4 TCP MSS (Max Segment Size): 1314 bytes
2016-02-22 17:49:47.336 On the TCP Listener (Port 0), a Client (IP address 192.168.0.106, Host name "192.168.0.106", Port number 1701) has connected.
2016-02-22 17:49:47.336 For the client (IP address: 192.168.0.106, host name: "192.168.0.106", port number: 1701), connection "CID-18-88922EEB76" has been created.
2016-02-22 17:49:47.337 SSL communication for connection "CID-18-88922EEB76" has been started. The encryption algorithm name is "(null)".
2016-02-22 17:49:47.345 [HUB "Teste1"] The connection "CID-18-88922EEB76" (IP address: 192.168.0.106, Host name: 192.168.0.106, Port number: 1701, Client name: "L2TP VPN Client", Version: 4.19, Build: 9599) is attempting to connect to the Virtual Hub. The auth type provided is "External server authentication" and the user name is "Nilo".
2016-02-22 17:49:47.345 [HUB "Teste1"] Connection "CID-18-88922EEB76": Successfully authenticated as user "Nilo".
2016-02-22 17:49:47.346 [HUB "Teste1"] Connection "CID-18-88922EEB76": The new session "SID-NILO-[L2TP]-5" has been created. (IP address: 192.168.0.106, Port number: 1701, Physical underlying protocol: "Legacy VPN - L2TP")
2016-02-22 17:49:47.346 [HUB "Teste1"] Session "SID-NILO-[L2TP]-5": The parameter has been set. Max number of TCP connections: 1, Use of encryption: Yes, Use of compression: No, Use of Half duplex communication: No, Timeout: 20 seconds.
2016-02-22 17:49:47.352 [HUB "Teste1"] Session "SID-NILO-[L2TP]-5": VPN Client details: (Client product name: "L2TP VPN Client", Client version: 419, Client build number: 9599, Server product name: "SoftEther VPN Server (32 bit)", Server version: 419, Server build number: 9599, Client OS name: "L2TP VPN Client", Client OS version: "-", Client product ID: "-", Client host name: "anonymous", Client IP address: "192.168.0.106", Client port number: 1701, Server host name: "192.168.0.201", Server IP address: "192.168.0.201", Server port number: 1701, Proxy host name: "", Proxy IP address: "0.0.0.0", Proxy port number: 0, Virtual Hub name: "Teste1", Client unique ID: "C672F7B8F742464797E7D5141937F6C5")
2016-02-22 17:49:47.360 L2TP PPP Session [192.168.0.106:1701]: Trying to request an IP address from the DHCP server.
2016-02-22 17:49:52.036 [HUB "Teste1"] Session "SID-NILO-4": The session has been terminated. The statistical information is as follows: Total outgoing data size: 6001 bytes, Total incoming data size: 10413 bytes.
2016-02-22 17:49:52.062 Connection "CID-16-CFC8CDE377" terminated by the cause "The VPN session has been deleted. It is possible that either the administrator disconnected the session or the connection from the client to the VPN Server has been disconnected." (code 11).
2016-02-22 17:49:52.062 Connection "CID-16-CFC8CDE377" has been terminated.
2016-02-22 17:49:52.062 The connection with the client (IP address 192.168.0.202, Port number 1229) has been disconnected.
2016-02-22 17:49:52.360 L2TP PPP Session [192.168.0.106:1701]: Acquiring an IP address from the DHCP server failed. To accept a PPP session, you need to have a DHCP server. Make sure that a DHCP server is working normally in the Ethernet segment which the Virtual Hub belongs to. If you do not have a DHCP server, you can use the Virtual DHCP function of the SecureNAT on the Virtual Hub instead.
2016-02-22 17:49:58.584 L2TP PPP Session [192.168.0.106:1701]: The VPN Client sent a packet though an IP address of the VPN Client hasn't been determined.
2016-02-22 17:49:58.584 L2TP PPP Session [192.168.0.106:1701]: A PPP protocol error occurred, or the PPP session has been disconnected.
2016-02-22 17:49:58.841 [HUB "Teste1"] Session "SID-NILO-[L2TP]-5": The session has been terminated. The statistical information is as follows: Total outgoing data size: 0 bytes, Total incoming data size: 1320 bytes.
2016-02-22 17:49:58.866 Connection "CID-18-88922EEB76" terminated by the cause "The VPN session has been deleted. It is possible that either the administrator disconnected the session or the connection from the client to the VPN Server has been disconnected." (code 11).
2016-02-22 17:49:58.866 Connection "CID-18-88922EEB76" has been terminated.
2016-02-22 17:49:58.866 The connection with the client (IP address 192.168.0.106, Port number 1701) has been disconnected.
2016-02-22 17:52:29.017 IPsec Client 2 (192.168.0.106:4500 -> 192.168.0.201:4500): This IPsec Client is deleted.
2016-02-22 17:52:29.017 IPsec IKE Session (IKE SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): This IKE SA is deleted.
2016-02-22 17:52:29.018 IPsec ESP Session (IPsec SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): This IPsec SA is deleted.
2016-02-22 17:52:29.018 IPsec ESP Session (IPsec SA) 2 (Client: 2) (192.168.0.106:4500 -> 192.168.0.201:4500): This IPsec SA is deleted.

I made all configurations using the Tutorial.
Can you help me how to make it work?

Thank you.

[PaulC]

This seems to be the same issue as here:

http://www.vpnusers.com/viewtopic.php?f=7&t=2698

Although, I'm not sure why these devices are struggling to get IP addresses allocated from the DHCP server (assuming it's configured correctly).

Windows doesn't seem to have a problem, but IOS and Android do (Although I've used both with my setup (using SecureNAT though) and they work fine.

[NiloRamirez]

Thanks for your hep, PaulC.
But I really can't make it work.
I turned off my firewall but the problem keeps.
Do you have any other idea to help me?
Another diferent configuration to use?

Thanks.

[PaulC]

What happens if you allow the hub to act as the DHCP server. Does it work correctly then?

[NiloRamirez]

Now it works.
Thank you PaulC.

:D