Package: ppp Version: 2.4.4rel-2 I'm trying to connect Windows systems as VPN roadwarriors to a gateway running ppp over l2tp over ipsec. The gateway is in Singapore, and has non-ideal internet connection (mainly, the MTU/MRU had to be lowered for some things to work properly).
For ppp, I set mtu and mru as well: ipcp-accept-local ipcp-accept-remote ms-dns 192.168.2.254 auth crtscts idle 1800 mtu 1200 mru 1200 nodefaultroute nodetach debug lock proxyarp connect-delay 5000 refuse-pap require-mschap-v2 plugin winbind.so ntlm_auth-helper '/usr/bin/ntlm_auth --helper-protocol=ntlm-server-1' However, when I try connecting with a client, network configuration times out; ppp log below. On the client, where ppp tracing is enabled, there are no packets traced after initial handshake; on the gateway, tcpdump initially shows ipsec traffic flowing both ways but then for roughly 25-30 seconds only packets coming in from the client, none going out anymore. Checking the ppp log, the client asks for a mru of 1400, larger than what the ppp configuration has set as mtu; pppd happily acknowledges it despite its lower mtu setting. It looks like the mtu configuration is ignored and pppd starts sending packets larger than what the tcp-ip (and thus ipsec) layer of the gateway can send. Regards, Filip Oct 18 15:24:00 scotos l2tpd[16079]: start_pppd: I'm running: Oct 18 15:24:00 scotos l2tpd[16079]: "/usr/sbin/pppd" Oct 18 15:24:00 scotos l2tpd[16079]: "passive" Oct 18 15:24:00 scotos l2tpd[16079]: "-detach" Oct 18 15:24:00 scotos l2tpd[16079]: "192.168.2.254:192.168.2.201" Oct 18 15:24:00 scotos l2tpd[16079]: "auth" Oct 18 15:24:00 scotos l2tpd[16079]: "name" Oct 18 15:24:00 scotos l2tpd[16079]: "scotos" Oct 18 15:24:00 scotos l2tpd[16079]: "debug" Oct 18 15:24:00 scotos l2tpd[16079]: "file" Oct 18 15:24:00 scotos l2tpd[16079]: "/etc/ppp/options.l2tpd.lns" Oct 18 15:24:00 scotos l2tpd[16079]: "/dev/ttyp0" Oct 18 15:24:00 scotos l2tpd[16079]: Oct 18 15:24:00 scotos pppd[16120]: using channel 7 Oct 18 15:24:00 scotos pppd[16120]: sent [LCP ConfReq id=0x1 <mru 1200> <asyncmap 0x0> <auth chap MS-v2> <magic 0x9fcb8fc7> <pcomp> <accomp>] Oct 18 15:24:00 scotos l2tpd[16079]: check_control: control, cid = 0, Ns = 4, Nr = 2 Oct 18 15:24:00 scotos pppd[16120]: rcvd [LCP ConfReq id=0x0 <mru 1400> <magic 0x2c3d20c0> <pcomp> <accomp> <callback CBCP> <mrru 1614> <endpoint [local:95.21.d7.70.e2.45.4b.6a.ad.23.8b.3d.b6.46.05.06.00.00.00.02]>] Oct 18 15:24:00 scotos pppd[16120]: sent [LCP ConfRej id=0x0 <callback CBCP> <mrru 1614>] Oct 18 15:24:00 scotos pppd[16120]: rcvd [LCP ConfAck id=0x1 <mru 1200> <asyncmap 0x0> <auth chap MS-v2> <magic 0x9fcb8fc7> <pcomp> <accomp>] Oct 18 15:24:00 scotos pppd[16120]: rcvd [LCP ConfReq id=0x1 <mru 1400> <magic 0x2c3d20c0> <pcomp> <accomp> <endpoint [local:95.21.d7.70.e2.45.4b.6a.ad.23.8b.3d.b6.46.05.06.00.00.00.02]>] Oct 18 15:24:00 scotos pppd[16120]: sent [LCP ConfAck id=0x1 <mru 1400> <magic 0x2c3d20c0> <pcomp> <accomp> <endpoint [local:95.21.d7.70.e2.45.4b.6a.ad.23.8b.3d.b6.46.05.06.00.00.00.02]>] Oct 18 15:24:00 scotos pppd[16120]: sent [LCP EchoReq id=0x0 magic=0x9fcb8fc7] Oct 18 15:24:00 scotos pppd[16120]: sent [CHAP Challenge id=0x53 <b22178cb0709f40803f1366fa7719b06>, name = "scotos"] Oct 18 15:24:01 scotos pppd[16120]: rcvd [LCP Ident id=0x2 magic=0x2c3d20c0 "MSRASV5.10"] Oct 18 15:24:01 scotos pppd[16120]: rcvd [LCP Ident id=0x3 magic=0x2c3d20c0 "MSRAS-0-GANYMEDES"] Oct 18 15:24:01 scotos pppd[16120]: rcvd [LCP EchoRep id=0x0 magic=0x2c3d20c0] Oct 18 15:24:01 scotos pppd[16120]: rcvd [CHAP Response id=0x53 <f7c5659f6a71325156fdffbe7153b92f0000000000000000f498dd47a4fa81a298eb90e7d726198586a90a77b374b46b00>, name = "DOMAIN\\username"] Oct 18 15:24:01 scotos pppd[16120]: sent [CHAP Success id=0x53 "S=31B24FEAAE17966BA335FEAEA577109E002F750E M=Access granted"] Oct 18 15:24:01 scotos pppd[16120]: sent [CCP ConfReq id=0x1 <deflate 15> <deflate(old#) 15> <bsd v1 15>] Oct 18 15:24:01 scotos pppd[16120]: sent [IPCP ConfReq id=0x1 <compress VJ 0f 01> <addr 192.168.2.254>] Oct 18 15:24:01 scotos pppd[16120]: rcvd [CCP ConfReq id=0x4 <mppe +H -M -S -L -D +C>] Oct 18 15:24:01 scotos pppd[16120]: sent [CCP ConfRej id=0x4 <mppe +H -M -S -L -D +C>] Oct 18 15:24:01 scotos pppd[16120]: rcvd [IPCP ConfReq id=0x5 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-wins 0.0.0.0> <ms-dns3 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:01 scotos pppd[16120]: sent [IPCP ConfRej id=0x5 <ms-wins 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:01 scotos pppd[16120]: rcvd [CCP ConfRej id=0x1 <deflate 15> <deflate(old#) 15> <bsd v1 15>] Oct 18 15:24:01 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:01 scotos pppd[16120]: rcvd [IPCP ConfRej id=0x1 <compress VJ 0f 01>] Oct 18 15:24:01 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:03 scotos pppd[16120]: rcvd [IPCP ConfReq id=0x6 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-wins 0.0.0.0> <ms-dns3 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:03 scotos pppd[16120]: sent [IPCP ConfRej id=0x6 <ms-wins 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:03 scotos pppd[16120]: rcvd [CCP ConfReq id=0x7 <mppe +H -M -S -L -D +C>] Oct 18 15:24:03 scotos pppd[16120]: sent [CCP ConfRej id=0x7 <mppe +H -M -S -L -D +C>] Oct 18 15:24:04 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:04 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:06 scotos pppd[16120]: rcvd [IPCP ConfReq id=0x8 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-wins 0.0.0.0> <ms-dns3 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:06 scotos pppd[16120]: sent [IPCP ConfRej id=0x8 <ms-wins 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:07 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:07 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:08 scotos pppd[16120]: rcvd [CCP ConfReq id=0x9 <mppe +H -M -S -L -D +C>] Oct 18 15:24:08 scotos pppd[16120]: sent [CCP ConfRej id=0x9 <mppe +H -M -S -L -D +C>] Oct 18 15:24:10 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:10 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:11 scotos pppd[16120]: rcvd [IPCP ConfReq id=0xa <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-wins 0.0.0.0> <ms-dns3 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:11 scotos pppd[16120]: sent [IPCP ConfRej id=0xa <ms-wins 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:13 scotos pppd[16120]: rcvd [CCP ConfReq id=0xb <mppe +H -M -S -L -D +C>] Oct 18 15:24:13 scotos pppd[16120]: sent [CCP ConfRej id=0xb <mppe +H -M -S -L -D +C>] Oct 18 15:24:13 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:13 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:16 scotos pppd[16120]: rcvd [IPCP ConfReq id=0xc <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-wins 0.0.0.0> <ms-dns3 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:16 scotos pppd[16120]: sent [IPCP ConfRej id=0xc <ms-wins 0.0.0.0> <ms-wins 0.0.0.0>] Oct 18 15:24:16 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:16 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:18 scotos pppd[16120]: rcvd [CCP ConfReq id=0xd <mppe +H -M -S -L -D +C>] Oct 18 15:24:18 scotos pppd[16120]: sent [CCP ConfRej id=0xd <mppe +H -M -S -L -D +C>] Oct 18 15:24:19 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:19 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:21 scotos pppd[16120]: rcvd [IPCP ConfReq id=0xe <addr 0.0.0.0>] Oct 18 15:24:21 scotos pppd[16120]: sent [IPCP ConfNak id=0xe <addr 192.168.2.201>] Oct 18 15:24:22 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:22 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:23 scotos pppd[16120]: rcvd [CCP ConfReq id=0xf <mppe +H -M -S -L -D +C>] Oct 18 15:24:23 scotos pppd[16120]: sent [CCP ConfRej id=0xf <mppe +H -M -S -L -D +C>] Oct 18 15:24:25 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:25 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:26 scotos pppd[16120]: rcvd [IPCP ConfReq id=0x10 <addr 0.0.0.0>] Oct 18 15:24:26 scotos pppd[16120]: sent [IPCP ConfNak id=0x10 <addr 192.168.2.201>] Oct 18 15:24:28 scotos pppd[16120]: rcvd [CCP ConfReq id=0x11 <mppe +H -M -S -L -D +C>] Oct 18 15:24:28 scotos pppd[16120]: sent [CCP ConfRej id=0x11 <mppe +H -M -S -L -D +C>] Oct 18 15:24:28 scotos pppd[16120]: sent [CCP ConfReq id=0x2] Oct 18 15:24:28 scotos pppd[16120]: sent [IPCP ConfReq id=0x2 <addr 192.168.2.254>] Oct 18 15:24:30 scotos pppd[16120]: sent [LCP EchoReq id=0x1 magic=0x9fcb8fc7] Oct 18 15:24:31 scotos pppd[16120]: rcvd [IPCP ConfReq id=0x12 <addr 0.0.0.0>] Oct 18 15:24:31 scotos pppd[16120]: sent [IPCP ConfNak id=0x12 <addr 192.168.2.201>] Oct 18 15:24:31 scotos pppd[16120]: sent [LCP TermReq id=0x2 "No network protocols running"] Oct 18 15:24:33 scotos pppd[16120]: rcvd [CCP ConfReq id=0x13 <mppe +H -M -S -L -D +C>] Oct 18 15:24:33 scotos pppd[16120]: Discarded non-LCP packet when LCP not open Oct 18 15:24:34 scotos pppd[16120]: sent [LCP TermReq id=0x3 "No network protocols running"] Oct 18 15:24:36 scotos pppd[16120]: rcvd [IPCP ConfReq id=0x14 <addr 0.0.0.0>] Oct 18 15:24:36 scotos pppd[16120]: Discarded non-LCP packet when LCP not open Oct 18 15:24:37 scotos l2tpd[16079]: child_handler : pppd exited for call 1 with code 16 Oct 18 15:24:38 scotos l2tpd[16079]: write_packet: tty is not open yet. Oct 18 15:24:41 scotos l2tpd[16079]: write_packet: tty is not open yet. Oct 18 15:24:42 scotos l2tpd[16079]: control_xmit: Maximum retries exceeded for tunnel 57393. Closing. Oct 18 15:24:43 scotos l2tpd[16079]: get_call: can't find call 43087 in tunnel 57393 Oct 18 15:24:47 scotos l2tpd[16079]: control_xmit: Unable to deliver closing message for tunnel 57393. Destroying anyway. Oct 18 15:24:48 scotos l2tpd[16079]: get_call:can't find tunnel 57393 Oct 18 15:24:48 scotos l2tpd[16079]: network_thread: unable to find call or tunnel to handle packet. call = 43087, tunnel = 57393 Dumping. Oct 18 15:24:52 scotos l2tpd[16079]: get_call:can't find tunnel 57393 Oct 18 15:24:52 scotos l2tpd[16079]: network_thread: unable to find call or tunnel to handle packet. call = 43087, tunnel = 57393 Dumping. Oct 18 15:24:56 scotos l2tpd[16079]: get_call:can't find tunnel 57393 Oct 18 15:24:56 scotos l2tpd[16079]: network_thread: unable to find call or tunnel to handle packet. call = 43087, tunnel = 57393 Dumping. Oct 18 15:25:06 scotos l2tpd[16079]: get_call:can't find tunnel 57393 Oct 18 15:25:06 scotos l2tpd[16079]: network_thread: unable to find call or tunnel to handle packet. call = 43087, tunnel = 57393 Dumping. -- System Information: Debian Release: testing/unstable APT prefers testing APT policy: (500, 'testing') Architecture: amd64 (x86_64) Shell: /bin/sh linked to /bin/bash Kernel: Linux 2.6.16-2-em64t-p4-smp Locale: LANG=en_SG.UTF-8, LC_CTYPE=en_SG.UTF-8 (charmap=UTF-8) Versions of packages ppp depends on: ii libc6 2.3.6.ds1-4 GNU C Library: Shared libraries ii libpam-modules 0.79-3.1 Pluggable Authentication Modules f ii libpam-runtime 0.79-3.1 Runtime support for the PAM librar ii libpam0g 0.79-3.1 Pluggable Authentication Modules l ii libpcap0.8 0.9.4-2 System interface for user-level pa ii netbase 4.25 Basic TCP/IP networking system ii procps 1:3.2.7-2 /proc file system utilities ii zlib1g 1:1.2.3-13 compression library - runtime http://slider.rack66.net/~mechanix/blog/ -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". 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