/var/log/messages: "CHAP authentication failed: Authentication failed"
/var/log/debug:
May 27 11:56:15 metamini pppd[5029]: Script /bin/true finished (pid 5030), status = 0x0
May 27 11:56:15 metamini pppd[5029]: using channel 269
May 27 11:56:16 metamini pppd[5029]: sent [LCP ConfReq id=0x1 <mru 1460> <asyncmap 0x0> <magic 0x4c036c1>]
May 27 11:56:16 metamini pppd[5029]: rcvd [LCP ConfReq id=0x1 <mru 1460> <asyncmap 0xa0000> <auth chap MD5> <magic 0xc3903538> <pcomp> <accomp>]
May 27 11:56:16 metamini pppd[5029]: sent [LCP ConfRej id=0x1 <pcomp> <accomp>]
May 27 11:56:16 metamini pppd[5029]: sent [LCP ConfRej id=0x1 <pcomp> <accomp>]
May 27 11:56:16 metamini pppd[5029]: rcvd [LCP ConfAck id=0x1 <mru 1460> <asyncmap 0x0> <magic 0x4c036c1>]
May 27 11:56:16 metamini pppd[5029]: rcvd [LCP ConfReq id=0x2 <mru 1460> <asyncmap 0xa0000> <auth chap MD5> <magic 0xc3903538>]
May 27 11:56:16 metamini pppd[5029]: sent [LCP ConfAck id=0x2 <mru 1460> <asyncmap 0xa0000> <auth chap MD5> <magic 0xc3903538>]
May 27 11:56:16 metamini pppd[5029]: sent [LCP ConfAck id=0x2 <mru 1460> <asyncmap 0xa0000> <auth chap MD5> <magic 0xc3903538>]
May 27 11:56:16 metamini pppd[5029]: sent [LCP EchoReq id=0x0 magic=0x4c036c1]
May 27 11:56:16 metamini pppd[5029]: sent [LCP EchoReq id=0x0 magic=0x4c036c1]
May 27 11:56:16 metamini pppd[5029]: rcvd [LCP EchoRep id=0x0 magic=0xc3903538]
May 27 11:56:16 metamini pppd[5029]: rcvd [CHAP Challenge id=0x1 <a4de975d27dba667f1797fee10390d82>, name = "bras239"]
May 27 11:56:16 metamini pppd[5029]: sent [CHAP Response id=0x1 <99c11b01354d49cb54b3d40579ed6f53>, name = "netawishmaster"]
May 27 11:56:16 metamini pppd[5029]: rcvd [CHAP Failure id=0x1 "Authentication failed"]
May 27 11:56:16 metamini pppd[5029]: sent [LCP TermReq id=0x2 "Failed to authenticate ourselves to peer"]
May 27 11:56:16 metamini pppd[5029]: rcvd [LCP TermAck id=0x2]

xl2tpd-1.2.6, на сколько я помню, пропатченная
xl2tpd[5022]: control_finish: Connection closed to 85.21.0.245, port 1701 (No application/session timer expired), Local: 23840, Remote: 48152
xl2tpd[5022]: Connecting to host tp.internet.beeline.ru, port 1701
xl2tpd[5022]: Connection established to 85.21.0.239, 1701. Local: 18245, Remote: 61141 (ref=0/0).
xl2tpd[5022]: Calling on tunnel 18245
xl2tpd[5022]: Call established with 85.21.0.239, Local: 12222, Remote: 45782, Serial: 2 (ref=0/0)
xl2tpd[5022]: start_pppd: I'm running:
xl2tpd[5022]: "/usr/sbin/pppd"
xl2tpd[5022]: "passive"
xl2tpd[5022]: "nodetach"
xl2tpd[5022]: ":"
xl2tpd[5022]: "name"
xl2tpd[5022]: "netawishmaster"
xl2tpd[5022]: "debug"
xl2tpd[5022]: "file"
xl2tpd[5022]: "/etc/ppp/options.corbina"
xl2tpd[5022]: "/dev/pts/5"
xl2tpd[5022]: handle_avps: don't know how to handle atribute 46.
xl2tpd[5022]: handle_avps: don't know how to handle atribute 104.
xl2tpd[5022]: control_finish: Connection closed to 85.21.0.239, serial 2 (Locally generated disconnect)
xl2tpd[5022]: Terminating pppd: sending TERM signal to pid 5029