I have also try to use this VPN connection from my Fedora Workstation and all work fine, seem a problem of router Vodafone Station.

This is a ping from server to V.S. when the V.S. is connected:

[root@s-virt tmp]# ping 192.168.11.100 PING 192.168.11.100 (192.168.11.100) 56(84) bytes of data. 64 bytes from 192.168.11.100: icmp_seq=1 ttl=64 time=63.3 ms mar 26 15:33:06 s-virt.ansaldi.loc kernel: mppe_decompress[0]: FLUSHED bit not set in stateless mode! 64 bytes from 192.168.11.100: icmp_seq=3 ttl=64 time=76.4 ms mar 26 15:33:08 s-virt.ansaldi.loc kernel: mppe_decompress[0]: FLUSHED bit not set in stateless mode! 64 bytes from 192.168.11.100: icmp_seq=5 ttl=64 time=63.8 ms mar 26 15:33:10 s-virt.ansaldi.loc kernel: mppe_decompress[0]: FLUSHED bit not set in stateless mode! 64 bytes from 192.168.11.100: icmp_seq=7 ttl=64 time=63.9 ms ^C --- 192.168.11.100 ping statistics --- 7 packets transmitted, 4 received, 42% packet loss, time 6002ms rtt min/avg/max/mdev = 63.364/66.895/76.414/5.508 ms

Many thanks

Il giorno lun, 26/03/2018 alle 13.03 +0200, Dario Lesca ha scritto:

I try to setup a PPTP VPN server on Centos 7 and from client a router Vodafone Station (Firmware 5.4.8.1.316.1.21)

On c7 I have install this:

[root@s-virt tmp]# rpm -q pptpd ppp pptpd-1.4.0-2.el7.x86_64 ppp-2.4.5-33.el7.x86_64

and setup all file and firewall like howto say. This now is my config:

/etc/pptpd.conf:option /etc/ppp/options.pptpd /etc/pptpd.conf:logwtmp /etc/pptpd.conf:localip 192.168.11.1 /etc/pptpd.conf:remoteip 192.168.11.100-109 /etc/ppp/options.pptpd:name pptpd /etc/ppp/options.pptpd:refuse-pap /etc/ppp/options.pptpd:refuse-chap /etc/ppp/options.pptpd:refuse-mschap /etc/ppp/options.pptpd:require-mschap-v2 /etc/ppp/options.pptpd:require-mppe-128 /etc/ppp/options.pptpd:lock /etc/ppp/options.pptpd:nobsdcomp /etc/ppp/options.pptpd:novj /etc/ppp/options.pptpd:novjccomp /etc/ppp/options.pptpd:nologfd /etc/ppp/chap-secrets:myuser pptpd mypass *

The connection from V.S. router to my c7 server work:

mar 26 12:50:28 s-virt.ansaldi.loc pptpd[26782]: CTRL: Client x.x.x.x control connection started mar 26 12:50:28 s-virt.ansaldi.loc pptpd[26782]: CTRL: Starting call (launching pppd, opening GRE) mar 26 12:50:28 s-virt.ansaldi.loc pppd[26783]: Plugin /usr/lib64/pptpd/pptpd-logwtmp.so loaded. mar 26 12:50:28 s-virt.ansaldi.loc pppd[26783]: pppd 2.4.5 started by root, uid 0 mar 26 12:50:28 s-virt.ansaldi.loc pppd[26783]: Using interface ppp0 mar 26 12:50:28 s-virt.ansaldi.loc pppd[26783]: Connect: ppp0 <--> /dev/pts/19 mar 26 12:50:28 s-virt.ansaldi.loc NetworkManager[1026]: <info> [1522061428.6946] manager: (ppp0): new Generic device ( /org/freedesktop/NetworkManager/Devices/40) mar 26 12:50:28 s-virt.ansaldi.loc pppd[26783]: peer from calling number x.x.x.x authorized mar 26 12:50:31 s-virt.ansaldi.loc pppd[26783]: MPPE 128-bit stateless compression enabled mar 26 12:50:34 s-virt.ansaldi.loc pppd[26783]: local IP address 192.168.11.1 mar 26 12:50:34 s-virt.ansaldi.loc pppd[26783]: remote IP address 192.168.11.100

But when I try to connect from a client (through the V. S. router) to my server via VPN, or ping it, on 4 ping only two work, and into log of server I see this error when the ping fail.

...

mar 26 12:00:50 s-virt.ansaldi.loc kernel: mppe_decompress[0]:

FLUSHED bit not set in stateless mode!

Someone have some suggest to resolve this problem ?

Many thanks