Good way to troubleshoot failed VPN connection

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spordniar
Posts: 3
Joined: Sat Mar 11, 2017 9:19 am

Good way to troubleshoot failed VPN connection

Post by spordniar » Sat Mar 11, 2017 9:29 am

Hi,

I have setup Softether VPN server, and was working well on Windows 10 64-bits before it broke.

For some reason, after reboot I cannot connect to VPN Server "localhost" anymore using the manager, seems like port 443 was occupied or something.

So I reinstalled the VPN Server again, and now I can connect back to localhost, setup everything as I once did, trying to connect from iPhone / Macbook as client, but without luck.

Mac gives the following log:

Sat Mar 11 01:18:22 2017 : l2tp_get_router_address
Sat Mar 11 01:18:22 2017 : l2tp_get_router_address 192.168.30.1 from dict 1
Sat Mar 11 01:18:22 2017 : L2TP connecting to server 'lonelybeast.softether.net' (73.70.191.194)...
Sat Mar 11 01:18:22 2017 : IPSec connection started
Sat Mar 11 01:18:22 2017 : IPSec phase 1 client started
Sat Mar 11 01:18:32 2017 : IPSec connection failed

And on both the Mac & iPhone, an error message would pop up saying:

"The L2TP-VPN server did not respond. Try reconnecting. If the problem continues, verify your settings and contact your Administrator."

I am just wondering whether there's an easier way to troubleshoot the connectivity issue from the server end (Win10) by checking the incoming connection issue and why the authentication would fail?

spordniar
Posts: 3
Joined: Sat Mar 11, 2017 9:19 am

Re: Good way to troubleshoot failed VPN connection

Post by spordniar » Sat Mar 11, 2017 9:46 am

Strange, after a while, the issue (unable to connect) just fixed itself, and I am not able to connect again. I didn't do anything except just waited a while.

spordniar
Posts: 3
Joined: Sat Mar 11, 2017 9:19 am

Re: Good way to troubleshoot failed VPN connection

Post by spordniar » Sat Mar 11, 2017 11:27 am

Somehow it stopped working again, here's the ppp.log for the session I was able to connect to the VPN, compare to the fail log, it seems like the server never replied.

Sat Mar 11 01:43:03 2017 : IPSec connection started
Sat Mar 11 01:43:03 2017 : IPSec phase 1 client started
Sat Mar 11 01:43:03 2017 : IPSec phase 1 server replied
Sat Mar 11 01:43:04 2017 : IPSec phase 2 started
Sat Mar 11 01:43:04 2017 : IPSec phase 2 established
Sat Mar 11 01:43:04 2017 : IPSec connection established
Sat Mar 11 01:43:04 2017 : L2TP sent SCCRQ
Sat Mar 11 01:43:04 2017 : L2TP received SCCRP
Sat Mar 11 01:43:04 2017 : L2TP sent SCCCN
Sat Mar 11 01:43:04 2017 : L2TP sent ICRQ
Sat Mar 11 01:43:04 2017 : L2TP received ICRP
Sat Mar 11 01:43:04 2017 : L2TP sent ICCN
Sat Mar 11 01:43:04 2017 : L2TP connection established.
Sat Mar 11 01:43:04 2017 : L2TP set port-mapping for en0, interface: 4, protocol: 0, privatePort: 0
Sat Mar 11 01:43:04 2017 : using link 0
Sat Mar 11 01:43:04 2017 : Using interface ppp0
Sat Mar 11 01:43:04 2017 : Connect: ppp0 <--> socket[34:18]
Sat Mar 11 01:43:04 2017 : sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xd4368f7> <pcomp> <accomp>]
Sat Mar 11 01:43:04 2017 : rcvd [LCP ConfReq id=0x0 <auth pap>]
Sat Mar 11 01:43:04 2017 : lcp_reqci: returning CONFACK.
Sat Mar 11 01:43:04 2017 : sent [LCP ConfAck id=0x0 <auth pap>]
Sat Mar 11 01:43:04 2017 : rcvd [LCP ConfRej id=0x1 <asyncmap 0x0> <magic 0xd4368f7> <pcomp> <accomp>]
Sat Mar 11 01:43:04 2017 : sent [LCP ConfReq id=0x2]
Sat Mar 11 01:43:04 2017 : rcvd [LCP ConfAck id=0x2]
Sat Mar 11 01:43:04 2017 : sent [LCP EchoReq id=0x0 magic=0x0]
Sat Mar 11 01:43:04 2017 : sent [PAP AuthReq id=0x1 user="nicole" password=<hidden>]
Sat Mar 11 01:43:04 2017 : rcvd [LCP EchoRep id=0x0 magic=0x0]
Sat Mar 11 01:43:05 2017 : rcvd [PAP AuthAck id=0x1]
Sat Mar 11 01:43:05 2017 : pap_rauthack: ignoring missing msg-length.
Sat Mar 11 01:43:05 2017 : PAP authentication succeeded
Sat Mar 11 01:43:05 2017 : sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]
Sat Mar 11 01:43:05 2017 : sent [IPV6CP ConfReq id=0x1 <addr fe80::bae8:56ff:fe32:b054>]
Sat Mar 11 01:43:05 2017 : sent [ACSCP ConfReq id=0x1 <route vers 16777216> <domain vers 16777216>]
Sat Mar 11 01:43:05 2017 : rcvd [IPCP ConfReq id=0x1 <addr 1.0.0.1>]
Sat Mar 11 01:43:05 2017 : ipcp: returning Configure-ACK
Sat Mar 11 01:43:05 2017 : sent [IPCP ConfAck id=0x1 <addr 1.0.0.1>]
Sat Mar 11 01:43:05 2017 : rcvd [LCP ProtRej id=0x2 80 57 01 01 00 0e 01 0a ba e8 56 ff fe 32 b0 54]
Sat Mar 11 01:43:05 2017 : rcvd [IPCP ConfNak id=0x1 <addr 192.168.30.13> <ms-dns1 8.8.8.8> <ms-dns3 8.8.4.4>]
Sat Mar 11 01:43:05 2017 : sent [IPCP ConfReq id=0x2 <addr 192.168.30.13> <ms-dns1 8.8.8.8> <ms-dns3 8.8.4.4>]
Sat Mar 11 01:43:05 2017 : rcvd [LCP ProtRej id=0x3 82 35 01 01 00 10 01 06 00 00 00 01 02 06 00 00 00 01]
Sat Mar 11 01:43:05 2017 : rcvd [IPCP ConfAck id=0x2 <addr 192.168.30.13> <ms-dns1 8.8.8.8> <ms-dns3 8.8.4.4>]
Sat Mar 11 01:43:05 2017 : ipcp: up
Sat Mar 11 01:43:05 2017 : local IP address 192.168.30.13
Sat Mar 11 01:43:05 2017 : remote IP address 1.0.0.1
Sat Mar 11 01:43:05 2017 : primary DNS address 8.8.8.8
Sat Mar 11 01:43:05 2017 : secondary DNS address 8.8.4.4
Sat Mar 11 01:43:05 2017 : Received protocol dictionaries
Sat Mar 11 01:43:05 2017 : sent [IP data <src addr 192.168.30.13> <dst addr 255.255.255.255> <BOOTP Request> <type INFORM> <client id 0x08000000010000> <parameters = 0x6 0x2c 0x2b 0x1 0xf9 0xf>]
Sat Mar 11 01:43:05 2017 : Received acsp/dhcp dictionaries
Sat Mar 11 01:43:05 2017 : Received acsp/dhcp dictionaries
Sat Mar 11 01:43:05 2017 : l2tp_wait_input: Address added. previous interface setting (name: en0, address: 10.231.64.49), current interface setting (name: ppp0, family: PPP, address: 192.168.30.13, subnet: 255.255.255.0, destination: 1.0.0.1).
Sat Mar 11 01:43:05 2017 : Committed PPP store on install command
Sat Mar 11 01:43:05 2017 : Committed PPP store on install command
Sat Mar 11 01:43:05 2017 : rcvd [IP data <src addr 192.168.30.1> <dst addr 192.168.30.13> <BOOTP Reply> <type ACK> <server id 0xc0a81e01> <domain name "hsd1.ca.comcast.net"> <subnet mask 255.255.255.0> <option 3> <option 6>]
Sat Mar 11 01:43:05 2017 : Received acsp/dhcp dictionaries
Sat Mar 11 01:43:05 2017 : l2tp_wait_input: Address deleted. previous interface setting (name: en0, address: 10.231.64.49), deleted interface setting (name: ppp0, family: PPP, address: 192.168.30.13, subnet: 255.255.255.0, destination: 1.0.0.1).
Sat Mar 11 01:43:05 2017 : l2tp_wait_input: Address added. previous interface setting (name: en0, address: 10.231.64.49), current interface setting (name: ppp0, family: PPP, address: 192.168.30.13, subnet: 255.255.255.0, destination: 1.0.0.1).
Sat Mar 11 01:43:05 2017 : Committed PPP store on install command
Sat Mar 11 01:43:08 2017 : L2TP port-mapping for en0, interfaceIndex: 0, Protocol: None, Private Port: 0, Public Address: 0, Public Port: 0, TTL: 0.
Sat Mar 11 01:43:08 2017 : L2TP port-mapping for en0 inconsistent. is Connected: 1, Previous interface: 4, Current interface 0

thisjun
Posts: 2458
Joined: Mon Feb 24, 2014 11:03 am

Re: Good way to troubleshoot failed VPN connection

Post by thisjun » Thu Mar 23, 2017 7:02 am

Please check the server log.

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