![]() ![]() Only see the L2TP traffic encrypted in UDP port 4500 or IP protocol 50 packets. Unless Wireshark has a Windows Filtering Platform (WFP) capture mechanism, such as that used by Microsoft Message Analyzer (MMA), then it should Wireshark, using an NDIS filter, should not be able to see this traffic since it should be in wrapped in ESP.The odd thing is that Wireshark sees a packet to UDP port 1701 this is odd for two reasons: The problem might just be in the negotiation of cryptographic parameters. "logman stop vpnprob -ets" stops the trace, after the problem has been reproduced. Logman start vpnprob -ets -pf vpn.lst -o vpntrace.etl Put those 3 lines in a file called vpn.lst (say) and issue the following command to start a trace: The following 3 trace providers (in a format suitable for use with logman.exe) are probably most helpful in this case: Since both client and server are Windows systems, the same tracing can be applied at either end. I always suggest using Event Tracing for Windows (ETW) to understand native VPN problems under Windows. How does the problem manifest itself? Any error messages, relevant log file entries can help to narrow down potential causes of the problem. Make sure that VPN Unlimited is allowed to access Public and Private networks. Click Change settings (you must have admin rights). The server never replies.ġ) It cant be a firewall ACL type issue on either the physical firewalls or the VPN server since the Android phone can connect.Ģ) It must be some NAT (NAT-T) issue?.but thats what the reg fix is for isnt it? In the Windows Search bar, type Allow an app and open Allow an app through Windows Firewall. I administrate this serverħ) The VPN server is also behind a router/firewall that is running NAT and also has the AssumeUDPEncapsulationContextOnSendRule reg fix appliedĨ) I have UDP ports 1701, 5 forwarded on the router/firewall to the server.ĩ) The router/firewalls at the server location and client location are both Unifi USGs and have VPN passthrough (ESP) enabled.ġ0) Running Wireshark on the server shows me that when I initiate the L2TP connection from the client, a packet comes in on UDP1701. This is when my Android phone is connected the same LAN as the PC (ie it is behind the same router/firewallĤ) I have a second Windows machine on the same LAN and that also cannot connect to the VPN.ĥ) I have set the "AssumeUDPEncapsulationContextOnSendRule" reg fix to 2 as per Microsofts suggestion for this problem.Ħ) The VPN server is a Windows 2016 Standard server running RRAS. Here are all the details:Ģ) I can connect to other L2TP VPNs from the same PCģ) I can connect to the VPN I am having a problem with from my Andoid phone. I cannot connect to a paticular L2TP/Ipsec based VPN. ![]()
0 Comments
Leave a Reply. |