Hi Sambuca,
yes, xl2tpd is running.
/var/log/auth.log
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: received Vendor ID payload [RFC 3947] method set to=109
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: received Vendor ID payload [draft-ietf-ipsec-nat-t-ike] method set to=110
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: ignoring unknown Vendor ID payload [8f8d83826d246b6fc7a8a6a428c11de8]
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: ignoring unknown Vendor ID payload [439b59f8ba676c4c7737ae22eab8f582]
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: ignoring unknown Vendor ID payload [4d1e0e136deafa34c4f3ea9f02ec7285]
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: ignoring unknown Vendor ID payload [80d0bb3def54565ee84645d4c85ce3ee]
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: ignoring unknown Vendor ID payload [9909b64eed937c6573de52ace952fa6b]
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: received Vendor ID payload [draft-ietf-ipsec-nat-t-ike-03] meth=108, but already using method 110
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: received Vendor ID payload [draft-ietf-ipsec-nat-t-ike-02] meth=107, but already using method 110
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: received Vendor ID payload [draft-ietf-ipsec-nat-t-ike-02_n] meth=106, but already using method 110
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: ignoring Vendor ID payload [FRAGMENTATION 80000000]
Nov 24 13:29:35 dcerouter pluto[21730]: packet from 186.242.129.142:500: received Vendor ID payload [Dead Peer Detection]
Nov 24 13:29:35 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: responding to Main Mode from unknown peer 186.242.129.142
Nov 24 13:29:35 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: transition from state STATE_MAIN_R0 to state STATE_MAIN_R1
Nov 24 13:29:35 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: STATE_MAIN_R1: sent MR1, expecting MI2
Nov 24 13:29:35 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: NAT-Traversal: Result using draft-ietf-ipsec-nat-t-ike (MacOS X): i am NATed
Nov 24 13:29:35 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: transition from state STATE_MAIN_R1 to state STATE_MAIN_R2
Nov 24 13:29:35 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: STATE_MAIN_R2: sent MR2, expecting MI3
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: ignoring informational payload, type IPSEC_INITIAL_CONTACT msgid=00000000
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: Main mode peer ID is ID_IPV4_ADDR: '186.242.129.142'
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: transition from state STATE_MAIN_R2 to state STATE_MAIN_R3
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: new NAT mapping for #18, was 186.242.129.142:500, now 186.242.129.142:4500
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: STATE_MAIN_R3: sent MR3, ISAKMP SA established {auth=OAKLEY_PRESHARED_KEY cipher=aes_256 prf=oakley_sha group=modp1024}
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: the peer proposed: 187.15.164.55/32:17/1701 -> 186.242.129.142/32:17/0
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: responding to Quick Mode proposal {msgid:0e352bfd}
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: us: 192.168.0.160[+S=C]:17/1701
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: them: 186.242.129.142[+S=C]:17/51077===?
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: transition from state STATE_QUICK_R0 to state STATE_QUICK_R1
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: STATE_QUICK_R1: sent QR1, inbound IPsec SA installed, expecting QI2
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: transition from state STATE_QUICK_R1 to state STATE_QUICK_R2
Nov 24 13:29:36 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #19: STATE_QUICK_R2: IPsec SA established transport mode {ESP=>0x0bfea5b5 <0x46b2c1c7 xfrm=AES_256-HMAC_SHA1 NATOA=none NATD=186.242.129.142:4500 DPD=none}
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: received Delete SA(0x0bfea5b5) payload: deleting IPSEC State #19
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: netlink recvfrom() of response to our XFRM_MSG_DELPOLICY message for policy eroute_connection delete inbound was too long: 100 > 36
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: netlink recvfrom() of response to our XFRM_MSG_DELPOLICY message for policy eroute_connection delete inbound was too long: 100 > 36
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: netlink recvfrom() of response to our XFRM_MSG_DELPOLICY message for policy unk255.10000@192.168.0.160 was too long: 168 > 36
Nov 24 13:29:58 dcerouter pluto[21730]: | raw_eroute result=0
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: received and ignored informational message
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142 #18: received Delete SA payload: deleting ISAKMP State #18
Nov 24 13:29:58 dcerouter pluto[21730]: "L2TP-PSK-NAT"[9] 186.242.129.142: deleting connection "L2TP-PSK-NAT" instance with peer 186.242.129.142 {isakmp=#0/ipsec=#0}
Nov 24 13:29:58 dcerouter pluto[21730]: packet from 186.242.129.142:4500: received and ignored informational message
Nov 24 13:30:01 dcerouter CRON[28937]: pam_unix(cron:session): session opened for user root by (uid=0)
Nov 24 13:30:01 dcerouter CRON[28938]: pam_unix(cron:session): session opened for user root by (uid=0)
Nov 24 13:30:01 dcerouter CRON[28939]: pam_unix(cron:session): session opened for user root by (uid=0)
Nov 24 13:30:03 dcerouter CRON[28939]: pam_unix(cron:session): session closed for user root
Nov 24 13:30:03 dcerouter CRON[28938]: pam_unix(cron:session): session closed for user root
Nov 24 13:30:10 dcerouter CRON[28937]: pam_unix(cron:session): session closed for user root
dcerouter_1031272:/var/log# ps ax | grep xl2
11310 pts/33 S+ 0:00 grep --color=auto xl2
23156 ? Ss 0:00 /usr/sbin/xl2tpd
/var/log/syslog (x2ltpd)
Nov 24 13:29:38 dcerouter xl2tpd[23156]: control_finish: Peer requested tunnel 17 twice, ignoring second one.
Nov 24 13:29:43 dcerouter xl2tpd[23156]: last message repeated 2 times
Nov 24 13:29:43 dcerouter xl2tpd[23156]: Maximum retries exceeded for tunnel 40741. Closing.
Nov 24 13:29:48 dcerouter xl2tpd[23156]: control_finish: Peer requested tunnel 17 twice, ignoring second one.
Nov 24 13:29:48 dcerouter xl2tpd[23156]: Connection 17 closed to 186.242.129.142, port 51077 (Timeout)
Nov 24 13:29:52 dcerouter xl2tpd[23156]: control_finish: Peer requested tunnel 17 twice, ignoring second one.
Nov 24 13:29:53 dcerouter xl2tpd[23156]: Unable to deliver closing message for tunnel 40741. Destroying anyway.
Nov 24 13:29:57 dcerouter xl2tpd[23156]: control_finish: Peer requested tunnel 17 twice, ignoring second one.
Did recheck the configs, but is not working....