i turned on debug but there is no helpful information in /var/log/messages:netstat -nlp|grep pptpd
tcp 0 0 0.0.0.0:1723 0.0.0.0:* LISTEN 2114/pptpd
loaded modules:cat /etc/pptpd.conf |grep debug
# TAG: debug
# Turns on (more) debugging to syslog
debug
cat /etc/ppp/options.pptpd |grep debug
# Enable connection debugging facilities.
debug
iptables rules:lsmod|grep gre
nf_conntrack_proto_gre 7003 1 nf_conntrack_pptp
nf_nat_proto_gre 3028 1 nf_nat_pptp
ip_gre 9575 0
ip_tunnel 12693 1 ip_gre
nf_nat 22759 5 nf_nat_pptp,nf_nat_proto_gre,nf_nat_ftp,ipt_MASQUERADE,iptable_nat
nf_conntrack 79758 10 nf_nat_pptp,nf_conntrack_pptp,nf_conntrack_proto_gre,nf_nat_ftp,nf_conntrack_ftp,ipt_MASQUERADE,iptable_nat,nf_nat,nf_conntrack_ipv4,xt_state
packets:#pptpd
iptables -A INPUT -p gre -j ACCEPT
iptables -A OUTPUT -p gre -j ACCEPT
iptables -A INPUT -s 0/0 -p udp --sport 1723 -j ACCEPT
iptables -A OUTPUT -d 0/0 -p udp --dport 1723 -j ACCEPT
iptables -A FORWARD -i ppp+ -m state --state NEW,RELATED,ESTABLISHED -j ACCEPT
tcpdump -i ppp0 dst port 1723
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on ppp0, link-type LINUX_SLL (Linux cooked), capture size 65535 bytes
23:16:54.673760 IP myip.8760 > serverip.pptp: Flags , seq 893685654, win 8192, options [mss 1412,nop,wscale 8,nop,nop,sackOK], length 0
23:16:57.683641 IP myip.8760 > serverip.pptp: Flags , seq 893685654, win 8192, options [mss 1412,nop,wscale 8,nop,nop,sackOK], length 0
23:17:03.690759 IP myip.8760 > serverip.pptp: Flags , seq 893685654, win 8192, options [mss 1412,nop,nop,sackOK], length 0
Windows vpn client gives 807 error.
Server side: 2.6.32-431.5.1.el6.x86_64 #1 SMP Wed Feb 12 00:41:43 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
Client side: Microsoft Windows [Version 6.2.9200]
Installed kernels:
cat /boot/grub/menu.lst |grep title
#title CentOS (2.6.32-358.14.1.el6.centos.plus.x86_64)
#title CentOS (3.13.2-1.el6.elrepo.x86_64)
#title CentOS (3.12.6-1.el6.elrepo.x86_64)
title CentOS (3.13.4-1.el6.elrepo.x86_64)
title CentOS (2.6.32-431.5.1.el6.x86_64)
title CentOS (2.6.32-431.3.1.el6.x86_64)
title CentOS (2.6.32-431.1.2.0.1.el6.x86_64)
title CentOS (2.6.32-358.18.1.el6.x86_64)