I am trying to set up a PPTP server on my VPS running Ubuntu 16.04. I have followed all the steps as detailed in the below two links:
https://help.ubuntu.com/community/PPTPServer
https://bobcares.com/blog/install-pptp-server-ubuntu/
However, I cannot VPN to my VPS neither from Windows 10, nor Ubunto 22.04, nor Android.
I am pretty experienced in System Administration though I am not good at networking, to be honest.
I need to take steps to pinpoint the problem.
The pptpd service seems functioning pretty well.
mike@vpsXXX:~$ netstat -ntl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:1723 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:1822 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:3306 0.0.0.0:* LISTEN
tcp6 0 0 :::80 :::* LISTEN
tcp6 0 0 :::1822 :::* LISTEN
mike@vpsXXX:~$ sudo service pptpd status
[sudo] password for mike:
● pptpd.service - PoPToP Point to Point Tunneling Server
Loaded: loaded (/lib/systemd/system/pptpd.service; enabled; vendor preset: enabled)
Active: active (running) since Sat 2023-07-08 09:22:42 EDT; 5h 56min ago
Main PID: 20218 (pptpd)
Tasks: 1
Memory: 156.0K
CPU: 12ms
CGroup: /system.slice/pptpd.service
└─20218 /usr/sbin/pptpd --fg
Jul 08 13:48:07 vpsXXX pptpd[20808]: CTRL: Client 198.199.93.96 control connection started
Jul 08 15:02:19 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:04:20 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:06:21 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:08:21 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:10:22 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:12:23 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:14:24 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:16:24 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
Jul 08 15:18:25 vpsXXX pptpd[20218]: MGR: dropped slow initial connection
mike@vpsXXX:~$
I need to take steps to pinpoint the problem. Any comment/clue is much appreciated.
I came across this How to fix MGR: dropped slow initial connection with pptpd? which seems relevant since I get the same warnings as check the pptpd's status.