pptp floods syslog

[GSMD]

Binary package hint: pptp-linux

After establishing a ppp connection to windows VPN server, syslog gets heavily flooded with messages like
--
Nov 29 03:43:04 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5014 (expecting 5013, lost or reordered)
Nov 29 03:43:08 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5069 (expecting 5068, lost or reordered)
Nov 29 03:43:10 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5110 (expecting 5106, lost or reordered)
Nov 29 03:43:18 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5237 (expecting 5233, lost or reordered)
Nov 29 03:43:22 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5297 (expecting 5293, lost or reordered)
Nov 29 03:43:22 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5303 (expecting 5302, lost or reordered)
Nov 29 03:43:23 server pptp[10604]: anon log[decaps_gre:pptp_gre.c:407]: accepting packet 5312 (expecting 5310, lost or reordered)
--
passing "--nobuffer" to pptp doesn't help.

[James Cameron (quozl)]

The --loglevel option for pptp was added in 2003 for this purpose, and was present from version 1.4.0-rc1 and onwards. The messages you show in this bug report are not printed if the --loglevel is reduced from the default 1 to the low 0. The messages indicate you have packet loss, and for efficiency of your tunnel the cause of the loss could be investigated.

[mEkdal (micke-ekdal)]

Havng the same experience. pptp to my office worked fine in 8.04 but is very slow and instable in 8.10.
Suspect a lott of many packages and I cannot figure out why, suspect a bug.

[James Cameron (quozl)]

Micke, what you describe has nothing to do with the original bug report ... which was an issue with the verbosity of the logs. But I can suggest some actions you can take.

1. Please downgrade temporarily to 8.04 if possible to verify for sure that it is the transition from 8.04 to 8.10 that caused your problem.

2. Please look for the cause of lost packets, using tcpdump or wireshark on your system's network interface, examining the sequence numbers and matching them against your pptp logs. If you see that packets are missing from the dump, then you can exclude the pptp package as the cause.

3. Please test with other tools such as ping, wget, or ssh, to see if you are experiencing lost packets purely on your system's network interface. If you are, then include the kernel and the network interface driver as a possible cause. Check for a later kernel or bugs against the kernel relating to your network card.

Otherwise, it sounds like you have an environmental problem, where the packets are being lost by routers or gateways between you and the server, as a result of your upgrade.

Consider raising a new bug "slow and unstable". Describe there what is unstable about it.