I know this may be slightly off-topic, but I feel like this may be related to iptable configuration. Has anyone here successfully implemented PoPTop (http://www.poptop.org) with Linux 2.4.18 with iptables? Is this problem related?
I am not sure what is causing this problem or if "GRE: Bad checksum from pppd" is the terminating error. This is running on a 2.4.18 patched kernel with mppe and mschap2 and PoPToP. Authentication appears to be working, but the connection is lost immediately after successful authentication. May 13 17:10:15 myserver pptpd[1658]: MGR: Launching /usr/local/sbin/pptpctrl to handle client May 13 17:10:15 myserver pptpd[1658]: CTRL: local address = 192.168.0.15 May 13 17:10:15 myserver pptpd[1658]: CTRL: remote address = 192.168.0.225 May 13 17:10:15 myserver pptpd[1658]: CTRL: pppd options file = /etc/ppp/options.pptp May 13 17:10:15 myserver pptpd[1658]: CTRL: Client 192.168.0.4 control connection started May 13 17:10:15 myserver pptpd[1658]: CTRL: Received PPTP Control Message (type: 1) May 13 17:10:15 myserver pptpd[1658]: CTRL: Made a START CTRL CONN RPLY packet May 13 17:10:15 myserver pptpd[1658]: CTRL: I wrote 156 bytes to the client. May 13 17:10:15 myserver pptpd[1658]: CTRL: Sent packet to client May 13 17:10:15 myserver pptpd[1658]: CTRL: Received PPTP Control Message (type: 7) May 13 17:10:15 myserver pptpd[1658]: CTRL: 0 min_bps, 1525 max_bps, 32 window size May 13 17:10:15 myserver pptpd[1658]: CTRL: Made a OUT CALL RPLY packet May 13 17:10:15 myserver pptpd[1658]: CTRL: Starting call (launching pppd, opening GRE) May 13 17:10:15 myserver pptpd[1658]: CTRL: pty_fd = 5 May 13 17:10:15 myserver pptpd[1658]: CTRL: tty_fd = 6 May 13 17:10:15 myserver pptpd[1659]: CTRL (PPPD Launcher): Connection speed = 115200 May 13 17:10:15 myserver pptpd[1658]: CTRL: I wrote 32 bytes to the client. May 13 17:10:16 myserver pptpd[1659]: CTRL (PPPD Launcher): local address = 192.168.0.15 May 13 17:10:16 myserver pptpd[1658]: CTRL: Sent packet to client May 13 17:10:16 myserver pptpd[1659]: CTRL (PPPD Launcher): remote address = 192.168.0.225 May 13 17:10:16 myserver pptpd[1658]: GRE: Bad checksum from pppd May 13 17:10:16 myserver pptpd[1658]: CTRL: Received PPTP Control Message (type: 15) May 13 17:10:16 myserver pptpd[1658]: CTRL: Got a SET LINK INFO packet with standard ACCMs May 13 17:10:19 myserver pptpd[1658]: CTRL: Received PPTP Control Message (type: 15) May 13 17:10:19 myserver pptpd[1658]: CTRL: Ignored a SET LINK INFO packet with real ACCMs! May 13 17:10:19 myserver pptpd[1658]: CTRL: Received PPTP Control Message (type: 15) May 13 17:10:19 myserver pptpd[1658]: CTRL: Got a SET LINK INFO packet with standard ACCMs May 13 17:10:22 myserver pptpd[1658]: Error reading from pppd: Input/output error May 13 17:10:22 myserver pptpd[1658]: CTRL: GRE read or PTY write failed (gre,pty)=(6,5) May 13 17:10:22 myserver pptpd[1658]: CTRL: Client 192.168.0.4 control connection finished May 13 17:10:22 myserver pptpd[1658]: CTRL: Exiting now May 13 17:10:22 myserver pptpd[1508]: MGR: Reaped child 1658 Thoughts? Here's some additional /etc/ppp/options.pptp: #debug lock auth +chap +chapms +chapms-v2 mppe-40 mppe-128 mppe-stateless TIA
