[pptp-server] frequent ppp disconnects

[Jeff Shanholtz]

Thanks for the tip. It appears that that did the trick. My connection
ran for almost 5 hours before I manually disconnected.


-----Original Message-----
From: Jordan Share [mailto:iso9 at phantasticant.com] 
Sent: Thursday, October 25, 2001 10:29 AM
To: Jeff Shanholtz; PoPToP List
Subject: RE: [pptp-server] frequent ppp disconnects


It looks like you are having problems with latency/packets dropping.

I have a user who is all but unable to use PPTP to tunnel into our LAN
because he is using Starband for his internet access.  The combination
of latency and packet loss seems to really screw up his connection.
Sometimes it works, sometimes it doesn't.

Anyway, the best thing I could think of to do is increase the time
between echo packets, and the number of echo packets that have to fail
before it drops the connection by putting this into my ppp/options file:

lcp-echo-failure 10
lcp-echo-interval 5

>From the man page for pppd:
       lcp-echo-failure n
              If this option is given, pppd will presume the peer
              to be dead if n LCP echo-requests are sent  without
              receiving a valid LCP echo-reply.  If this happens,
              pppd will terminate the connection.   Use  of  this
              option  requires a non-zero value for the lcp-echo-
              interval parameter.  This option  can  be  used  to
              enable pppd to terminate after the physical connec-
              tion has been broken (e.g., the modem has hung  up)
              in situations where no hardware modem control lines
              are available.

       lcp-echo-interval n
              If this option is given,  pppd  will  send  an  LCP
              echo-request  frame  to  the  peer every n seconds.
              Normally the  peer  should  respond  to  the  echo-
              request  by sending an echo-reply.  This option can
              be used with the lcp-echo-failure option to  detect
              that the peer is no longer connected.

Jordan

-----Original Message-----
From: pptp-server-admin at lists.schulte.org
[mailto:pptp-server-admin at lists.schulte.org]On Behalf Of Jeff Shanholtz
Sent: Wednesday, October 24, 2001 9:25 PM
To: PoPToP List
Subject: [pptp-server] frequent ppp disconnects


My vpn client is frequently disconnecting. It can happen as often as
every few minutes, but usually it takes more like 15 or 20 minutes. Once
I was able to stay connected for 3-4 hours before the disconnection, but
that is the only time I've been able to maintain a relatively long
connection. I'm using 1.1.2 and pppd 2.4.1 on RH 7.1. I haven't
installed any of the patches. Other than the frequent disconnects,
networking works great. How does one track down such a problem? Does
anyone know the solution? Does anyone think it would (or wouldn't) be
worth going back to the "stable" build of poptop?

Here's a few lines from /var/log/messages:

Oct 24 14:10:20 shane pptpd[6771]: Buffering out-of-order packet; got
67888 after 67885
Oct 24 14:10:20 shane pptpd[6771]: Buffering out-of-order packet; got
67889 after 67885
Oct 24 14:10:20 shane pptpd[6771]: Buffering out-of-order packet; got
67890 after 67885
Oct 24 14:10:20 shane pptpd[6771]: Gave up waiting for 2 lost packets
beginning with 67886
Oct 24 14:10:52 shane pppd[6772]: No response to 3 echo-requests
Oct 24 14:10:52 shane pppd[6772]: Serial link appears to be
disconnected.
Oct 24 14:10:58 shane pppd[6772]: Connection terminated.