1 .\" manual page [] for pppd 2.0
2 .\" $Id: pppd.8,v 1.16 1995/12/18 03:48:04 paulus Exp $
4 .\" SS subsection heading
6 .\" IP indented paragraph
10 pppd \- Point to Point Protocol daemon
22 The Point-to-Point Protocol (PPP) provides a method for transmitting
23 datagrams over serial point-to-point links. PPP
24 is composed of three parts: a method for encapsulating datagrams over
25 serial links, an extensible Link Control Protocol (LCP), and
26 a family of Network Control Protocols (NCP) for establishing
27 and configuring different network-layer protocols.
29 The encapsulation scheme is provided by driver code in the kernel.
31 provides the basic LCP, authentication support, and an
32 NCP for establishing and configuring the Internet Protocol (IP)
33 (called the IP Control Protocol, IPCP).
34 .SH FREQUENTLY USED OPTIONS
37 Communicate over the named device. The string "/dev/"
38 is prepended if necessary. If no device name is given,
39 or if the name of the controlling terminal is given,
41 will use the controlling terminal, and will not fork to put itself in
45 Set the baud rate to <speed> (a decimal number). On systems such as
46 4.4BSD and NetBSD, any speed can be specified. Other systems
47 (e.g. SunOS) allow only a limited set of speeds.
50 Set the async character map to <map>.
51 This map describes which control characters cannot be successfully
52 received over the serial line.
54 will ask the peer to send these characters as a 2-byte escape sequence.
55 The argument is a 32 bit hex number
56 with each bit representing a character to escape.
57 Bit 0 (00000001) represents the character 0x00;
58 bit 31 (80000000) represents the character 0x1f or ^_.
59 If multiple \fBasyncmap\fR options are
60 given, the values are ORed together.
61 If no \fBasyncmap\fR option is given, no async character map will be
62 negotiated for the receive direction; the peer should then escape
63 \fIall\fR control characters.
66 Require the peer to authenticate itself before allowing network
67 packets to be sent or received.
70 Use the executable or shell command specified by \fI<p>\fR to set up the
71 serial line. This script would typically use the chat(8) program to
72 dial the modem and start the remote ppp session.
75 Use hardware flow control (i.e. RTS/CTS) to control the flow of data
76 on the serial port. If neither the \fBcrtscts\fR nor the
77 \fB\-crtscts\fR option is given, the hardware flow control setting for
78 the serial port is left unchanged.
81 Add a default route to the system routing tables, using the peer as
82 the gateway, when IPCP negotiation is successfully completed.
83 This entry is removed when the PPP connection is broken.
86 Run the executable or shell command specified by \fI<p>\fR after
87 \fIpppd\fR has terminated the link. This script could, for example,
88 issue commands to the modem to cause it to hang up if hardware modem
89 control signals were not available.
91 .B escape \fIxx,yy,...
92 Specifies that certain characters should be escaped on transmission
93 (regardless of whether the peer requests them to be escaped with its
94 async control character map). The characters to be escaped are
95 specified as a list of hex numbers separated by commas. Note that
96 almost any character can be specified for the \fBescape\fR option,
97 unlike the \fBasyncmap\fR option which only allows control characters
98 to be specified. The characters which may not be escaped are those
99 with hex values 0x20 - 0x3f or 0x5e.
102 Read options from file <f> (the format is described below).
105 Specifies that \fIpppd\fR should create a UUCP-style lock file for the
106 serial device to ensure exclusive access to the device.
109 Set the MRU [Maximum Receive Unit] value to <n> for negotiation.
111 will ask the peer to send packets of no more than <n> bytes. The
112 minimum MRU value is 128. The default MRU value is 1500. A value of
113 296 is recommended for slow links (40 bytes for TCP/IP header + 256
117 Set the MTU [Maximum Transmit Unit] value to \fI<n>\fR. Unless the
118 peer requests a smaller value via MRU negotiation, \fIpppd\fR will
119 request that the kernel networking code send data packets of no more
120 than \fIn\fR bytes through the PPP network interface.
123 Set the interface netmask to <n>, a 32 bit netmask in "decimal dot"
124 notation (e.g. 255.255.255.0). If this option is given, the value
125 specified is ORed with the default netmask. The default netmask is
126 chosen based on the negotiated remote IP address; it is the
127 appropriate network mask for the class of the remote IP address, ORed
128 with the netmasks for any non point-to-point network interfaces in the
129 system which are on the same network.
132 Enables the "passive" option in the LCP. With this option,
134 will attempt to initiate a connection; if no reply is received from
137 will then just wait passively for a valid LCP packet from the peer
138 (instead of exiting, as it does without this option).
143 will not transmit LCP packets to initiate a connection until a valid
144 LCP packet is received from the peer (as for the `passive' option with
145 ancient versions of \fIpppd\fR).
148 .I <local_IP_address>\fB:\fI<remote_IP_address>
149 Set the local and/or remote interface IP addresses. Either one may be
150 omitted. The IP addresses can be specified with a host name or in
151 decimal dot notation (e.g. 150.234.56.78). The default local
152 address is the (first) IP address of the system (unless the
154 option is given). The remote address will be obtained from the peer
155 if not specified in any option. Thus, in simple cases, this option is
156 not required. If a local and/or remote IP address is specified with
159 will not accept a different value from the peer in the IPCP
160 negotiation, unless the
163 .B ipcp-accept-remote
164 options are given, respectively.
167 Disable Address/Control compression negotiation (use default, i.e.
168 address/control field compression disabled).
171 Don't request or allow negotiation of any options for LCP and IPCP (use
175 Disable asyncmap negotiation (use the default asyncmap, i.e. escape
176 all control characters).
183 Request that the peer compress packets that it sends, using the
184 BSD-Compress scheme, with a maximum code size of \fInr\fR bits, and
185 agree to compress packets sent to the peer with a maximum code size of
186 \fInt\fR bits. If \fInt\fR is not specified, it defaults to the value
187 given for \fInr\fR. Values in the range 9 to 15 may be used for
188 \fInr\fR and \fInt\fR; larger values give better compression but
189 consume more kernel memory for compression dictionaries.
190 Alternatively, a value of 0 for \fInr\fR or \fInt\fR disables
191 compression in the corresponding direction.
194 Disables compression; \fBpppd\fR will not request or agree to compress
195 packets using the BSD-Compress scheme.
198 Require the peer to authenticate itself using CHAP [Cryptographic
199 Handshake Authentication Protocol] authentication.
202 Don't agree to authenticate using CHAP.
204 .B chap-interval \fI<n>
205 If this option is given,
207 will rechallenge the peer every <n> seconds.
209 .B chap-max-challenge \fI<n>
210 Set the maximum number of CHAP challenge transmissions to <n> (default
213 .B chap-restart \fI<n>
214 Set the CHAP restart interval (retransmission timeout for challenges)
215 to <n> seconds (default 3).
218 Disable hardware flow control (i.e. RTS/CTS) on the serial port. If
219 neither the \fBcrtscts\fR nor the \fB\-crtscts\fR option is given,
220 the hardware flow control setting for the serial port is left
224 Increase debugging level (same as the \fBdebug\fR option).
227 Increase debugging level (same as \fB\-d\fR).
228 If this option is given, \fIpppd\fR will log the contents of all
229 control packets sent or received in a readable form. The packets are
230 logged through syslog with facility \fIdaemon\fR and level
231 \fIdebug\fR. This information can be directed to a file by setting up
232 /etc/syslog.conf appropriately (see syslog.conf(5)).
235 Disable the \fBdefaultroute\fR option. The system administrator who
236 wishes to prevent users from creating default routes with \fIpppd\fR
237 can do so by placing this option in the /etc/ppp/options file.
240 Don't fork to become a background process (otherwise
242 will do so if a serial device other than its controlling terminal is
248 is acting as a server for Microsoft Windows clients, this option
251 to supply one or two DNS (Domain Name Server) addresses to the
252 clients. The first instance of this option specifies the primary DNS
253 address; the second instance (if given) specifies the secondary DNS
257 Append the domain name <d> to the local host name for authentication
258 purposes. For example, if gethostname() returns the name porsche, but the
259 fully qualified domain name is porsche.Quotron.COM, you would use the
260 domain option to set the domain name to Quotron.COM.
263 Disable IPCP negotiation and IP communication. This option should
264 only be required if the peer is buggy and gets confused by requests
267 for IPCP negotiation.
270 Enable the IPXCP and IPX protocols. Under Linux, this is the default
271 condition if your kernel supports IPX. This option is presently only
272 supported under Linux.
275 Disable the IPXCP and IPX protocols. This option should only be
276 required if the peer is buggy and gets confused by requests from
278 for IPXCP negotiation.
283 will accept the peer's idea of our local IP address, even if the
284 local IP address was specified in an option.
286 .B ipcp-accept-remote
289 will accept the peer's idea of its (remote) IP address, even if the
290 remote IP address was specified in an option.
292 .B ipcp-max-configure \fI<n>
293 Set the maximum number of IPCP configure-request transmissions to <n>
296 .B ipcp-max-failure \fI<n>
297 Set the maximum number of IPCP configure-NAKs returned before starting
298 to send configure-Rejects instead to <n> (default 10).
300 .B ipcp-max-terminate \fI<n>
301 Set the maximum number of IPCP terminate-request transmissions to <n>
304 .B ipcp-restart \fI<n>
305 Set the IPCP restart interval (retransmission timeout) to <n> seconds
309 Provides an extra parameter to the ip-up and ip-down scripts. If this
310 option is given, the \fIstring\fR supplied is given as the 6th
311 parameter to those scripts.
313 .B ipx-network \fI<n>
314 Set the IPX network number in the IPXCP configure request frame to
315 <n>. There is no valid default. If this option is not specified then
316 the network number is obtained from the peer. If the peer does not
317 have the network number, the IPX protocol will not be started. This is
318 a hexadecimal number and is entered without any leading sequence such
319 as 0x. It is related to the \fIipxcp-accept-network\fR option.
321 .B ipx-node \fI<n>:<m>
322 Set the IPX node numbers. The two node numbers are separated from each
323 other with a colon character. The first number <n> is the local node
324 number. The second number <m> is the peer's node number. Each node number
325 is a hexadecimal number, to the maximum of ten significant digits. The
326 node numbers on the ipx-network must be unique. There is no valid
327 default. If this option is not specified then the node number is
328 obtained from the peer. This option is a related to the
329 \fIipxcp-accept-local\fR and \fIipxcp-accept-remote\fR options.
331 .B ipx-router-name \fI<string>
332 Set the name of the router. This is a string and is sent to the peer
335 .B ipx-routing \fI<n>
336 Set the routing protocol to be received by this option. More than one
337 instance of \fIipx-routing\fR may be specified. The '\fInone\fR'
338 option (0) may be specified as the only instance of ipx-routing. The
339 values may be \fI0\fR for \fINONE\fR, \fI2\fR for \fIRIP/SAP\fR, and
340 \fI4\fR for \fINLSP\fR.
342 .B ipxcp-accept-local
343 Accept the peer's NAK for the node number specified in the ipx-node
344 option. If a node number was specified, and non-zero, the default is
345 to insist that the value be used. If you include this option then you
346 will permit the peer to override the entry of the node number.
348 .B ipxcp-accept-network
349 Accept the peer's NAK for the network number specified in the
350 ipx-network option. If a network number was specified, and non-zero, the
351 default is to insist that the value be used. If you include this
352 option then you will permit the peer to override the entry of the node
355 .B ipxcp-accept-remote
356 Use the peer's network number specified in the configure request
357 frame. If a node number was specified for the peer and this option was
358 not specified, the peer will be forced to use the value which you have
361 .B ipxcp-max-configure \fI<n>
362 Set the maximum number of IPXCP configure request frames which the
363 system will send to <n>. The default is 10.
365 .B ipxcp-max-failure \fI<n>
366 Set the maximum number of IPXCP NAK frames which the local system will
367 send before it rejects the options. The default value is 3.
369 .B ipxcp-max-terminate \fI<n>
370 Set the maximum nuber of IPXCP terminate request frames before the
371 local system considers that the peer is not listening to them. The
375 Enable debugging code in the kernel-level PPP driver. The argument
376 \fIn\fR is a number which is the sum of the following values: 1 to
377 enable general debug messages, 2 to request that the contents of
378 received packets be printed, and 4 to request that the contents of
379 transmitted packets be printed.
381 .B lcp-echo-failure \fI<n>
382 If this option is given, \fIpppd\fR will presume the peer to be dead
383 if \fIn\fR LCP echo-requests are sent without receiving a valid LCP
384 echo-reply. If this happens, \fIpppd\fR will terminate the
385 connection. Use of this option requires a non-zero value for the
386 \fIlcp-echo-interval\fR parameter. This option can be used to enable
387 \fIpppd\fR to terminate after the physical connection has been broken
388 (e.g., the modem has hung up) in situations where no hardware modem
389 control lines are available.
391 .B lcp-echo-interval \fI<n>
392 If this option is given, \fIpppd\fR will send an LCP echo-request
393 frame to the peer every \fIn\fR seconds. Under Linux, the
394 echo-request is sent when no packets have been received from the peer
395 for \fIn\fR seconds. Normally the peer should respond to the
396 echo-request by sending an echo-reply. This option can be used with
397 the \fIlcp-echo-failure\fR option to detect that the peer is no longer
400 .B lcp-max-configure \fI<n>
401 Set the maximum number of LCP configure-request transmissions to <n>
404 .B lcp-max-failure \fI<n>
405 Set the maximum number of LCP configure-NAKs returned before starting
406 to send configure-Rejects instead to <n> (default 10).
408 .B lcp-max-terminate \fI<n>
409 Set the maximum number of LCP terminate-request transmissions to <n>
412 .B lcp-restart \fI<n>
413 Set the LCP restart interval (retransmission timeout) to <n> seconds
417 Don't use the modem control lines. With this option,
419 will ignore the state of the CD (Carrier Detect) signal from the modem and
420 will not change the state of the DTR (Data Terminal Ready) signal.
423 Use the system password database for authenticating the peer using
424 PAP, and record the user in the system wtmp file.
427 Use the modem control lines. This option is the default. With this
430 will wait for the CD (Carrier Detect) signal from the modem to be asserted
431 when opening the serial device
432 (unless a connect script is specified), and it will drop the DTR (Data
433 Terminal Ready) signal briefly when the connection is terminated and before
434 executing the connect script.
435 On Ultrix, this option implies hardware
436 flow control, as for the \fBcrtscts\fR option.
439 Disable magic number negotiation. With this option,
441 cannot detect a looped-back line.
444 Disable MRU [Maximum Receive Unit] negotiation. With this option,
445 \fIpppd\fR will use the default MRU value of 1500 bytes.
448 Set the name of the local system for authentication purposes to <n>.
451 Disables the default behaviour when no local IP address is specified,
452 which is to determine (if possible) the local IP address from the
453 hostname. With this option, the peer will have to supply the local IP
454 address during IPCP negotiation (unless it specified explicitly on the
455 command line or in an options file).
463 Require the peer to authenticate itself using PAP.
466 Don't agree to authenticate using PAP.
469 Indicates that all secrets in the /etc/ppp/pap-secrets file which
470 are used for checking the identity of the peer are encrypted, and thus
471 pppd should not accept a password which (before encryption) is
472 identical to the secret from the /etc/ppp/pap-secrets file.
474 .B pap-max-authreq \fI<n>
475 Set the maximum number of PAP authenticate-request transmissions to
478 .B pap-restart \fI<n>
479 Set the PAP restart interval (retransmission timeout) to <n> seconds
482 .B pap-timeout \fI<n>
483 Set the maximum time that
485 will wait for the peer to authenticate itself with PAP to
486 <n> seconds (0 means no limit).
489 Disable protocol field compression negotiation (use default, i.e.
490 protocol field compression disabled).
493 Do not exit after a connection is terminated; instead try to reopen
497 Attempt to request that the peer send frames which
498 have been compressed using Predictor-1 compression. This option will
499 be ignored unless Predictor-1 code has been loaded into the kernel.
502 Do not accept or agree to Predictor-1 comprssion.
505 Add an entry to this system's ARP [Address Resolution Protocol] table
506 with the IP address of the peer and the Ethernet address of this
510 Disable the \fBproxyarp\fR option. The system administrator who
511 wishes to prevent users from creating proxy ARP entries with
512 \fIpppd\fR can do so by placing this option in the /etc/ppp/options
516 Set the assumed name of the remote system for authentication purposes
520 Agree to authenticate using PAP [Password Authentication Protocol] if
521 requested by the peer, and
522 use the data in file <p> for the user and password to send to the
523 peer. The file contains the remote user name, followed by a newline,
524 followed by the remote password, followed by a newline. This option
528 Enforce the use of the hostname as the name of the local system for
529 authentication purposes (overrides the
534 Set the user name to use for authenticating this machine with the peer
538 Disable negotiation of Van Jacobson style TCP/IP header compression (use
539 default, i.e. no compression).
542 Disable the connection-ID compression option in Van Jacobson style
543 TCP/IP header compression. With this option, \fIpppd\fR will not omit
544 the connection-ID byte from Van Jacobson compressed TCP/IP headers,
545 nor ask the peer to do so.
548 Sets the number of connection slots to be used by the Van Jacobson
549 TCP/IP header compression and decompression code to \fIn\fR, which
550 must be between 2 and 16 (inclusive).
553 Use software flow control (i.e. XON/XOFF) to control the flow of data on
554 the serial port. This option is only implemented on Linux systems
557 Options can be taken from files as well as the command line.
559 reads options from the files /etc/ppp/options and ~/.ppprc before
560 looking at the command line. An options file is parsed into a series
561 of words, delimited by whitespace. Whitespace can be included in a
562 word by enclosing the word in quotes ("). A backslash (\\) quotes the
563 following character. A hash (#) starts a comment, which continues
564 until the end of the line.
567 provides system administrators with sufficient access control that PPP
568 access to a server machine can be provided to legitimate users without
569 fear of compromising the security of the server or the network it's
570 on. In part this is provided by the /etc/ppp/options file, where the
571 administrator can place options to require authentication whenever
573 is run, and in part by the PAP and CHAP secrets files, where the
574 administrator can restrict the set of IP addresses which individual
577 The default behaviour of
579 is to agree to authenticate if requested, and to not
580 require authentication from the peer. However,
583 authenticate itself with a particular protocol if it has no secrets
584 which could be used to do so.
586 Authentication is based on secrets, which are selected from secrets
587 files (/etc/ppp/pap-secrets for PAP, /etc/ppp/chap-secrets for CHAP).
588 Both secrets files have the same format, and both can store secrets
589 for several combinations of server (authenticating peer) and client
590 (peer being authenticated). Note that
593 and client, and that different protocols can be used in the two
594 directions if desired.
596 A secrets file is parsed into words as for a options file. A secret
597 is specified by a line containing at least 3 words, in the order
598 client name, server name, secret. Any following words on the same line are
599 taken to be a list of acceptable IP addresses for that client. If
600 there are only 3 words on the line, it is assumed that any IP address
601 is OK; to disallow all IP addresses, use "-". If the secret starts
602 with an `@', what follows is assumed to be the name of a file from
603 which to read the secret. A "*" as the client or server name matches
604 any name. When selecting a secret, \fIpppd\fR takes the best match, i.e.
605 the match with the fewest wildcards.
607 Thus a secrets file contains both secrets for use in authenticating
608 other hosts, plus secrets which we use for authenticating ourselves to
609 others. Which secret to use is chosen based on the names of the host
610 (the `local name') and its peer (the `remote name'). The local name
613 if the \fBusehostname\fR option is given,
614 then the local name is the hostname of this machine
615 (with the domain appended, if given)
617 else if the \fBname\fR option is given,
618 then use the argument of the first \fBname\fR option seen
620 else if the local IP address is specified with a hostname,
623 else use the hostname of this machine (with the domain appended, if given)
625 When authenticating ourselves using PAP, there is also a `username'
626 which is the local name by default, but can be set with the \fBuser\fR
627 option or the \fB+ua\fR option.
629 The remote name is set as follows:
631 if the \fBremotename\fR option is given,
632 then use the argument of the last \fBremotename\fR option seen
634 else if the remote IP address is specified with a hostname,
635 then use that host name
637 else the remote name is the null string "".
639 Secrets are selected from the PAP secrets file as follows:
642 For authenticating the peer, look for a secret with client ==
643 username specified in the PAP authenticate-request, and server ==
647 For authenticating ourselves to the peer, look for a secret with
648 client == our username, server == remote name.
650 When authenticating the peer with PAP, a secret of "" matches any
651 password supplied by the peer. If the password doesn't match the
652 secret, the password is encrypted using crypt() and checked against
653 the secret again; thus secrets for authenticating the peer can be
654 stored in encrypted form. If the \fBpapcrypt\fR option is given, the
655 first (unencrypted) comparison is omitted, for better security.
657 If the \fBlogin\fR option was specified, the
658 username and password are also checked against the system password
659 database. Thus, the system administrator can set up the pap-secrets
660 file to allow PPP access only to certain users, and to restrict the
661 set of IP addresses that each user can use. Typically, when using the
662 \fBlogin\fR option, the secret in /etc/ppp/pap-secrets would be "", to
663 avoid the need to have the same secret in two places.
665 Secrets are selected from the CHAP secrets file as follows:
668 For authenticating the peer, look for a secret with client == name
669 specified in the CHAP-Response message, and server == local name.
672 For authenticating ourselves to the peer, look for a secret with
673 client == local name, and server == name specified in the
674 CHAP-Challenge message.
676 Authentication must be satisfactorily completed before IPCP (or any
677 other Network Control Protocol) can be started. If authentication
678 fails, \fIpppd\fR will terminated the link (by closing LCP). If IPCP
679 negotiates an unacceptable IP address for the remote host, IPCP will
680 be closed. IP packets can only be sent or received when IPCP is open.
682 In some cases it is desirable to allow some hosts which can't
683 authenticate themselves to connect and use one of a restricted set of
684 IP addresses, even when the local host generally requires
685 authentication. If the peer refuses to authenticate itself when
686 requested, \fIpppd\fR takes that as equivalent to authenticating with
687 PAP using the empty string for the username and password. Thus, by
688 adding a line to the pap-secrets file which specifies the empty string
689 for the client and password, it is possible to allow restricted access
690 to hosts which refuse to authenticate themselves.
693 When IPCP negotiation is completed successfully,
695 will inform the kernel of the local and remote IP addresses for the
696 ppp interface. This is sufficient to create a
697 host route to the remote end of the link, which will enable the peers
698 to exchange IP packets. Communication with other machines generally
699 requires further modification to routing tables and/or ARP (Address
700 Resolution Protocol) tables. In some cases this will be done
701 automatically through the actions of the \fIrouted\fR or \fIgated\fR
702 daemons, but in most cases some further intervention is required.
704 Sometimes it is desirable
705 to add a default route through the remote host, as in the case of a
706 machine whose only connection to the Internet is through the ppp
707 interface. The \fBdefaultroute\fR option causes \fIpppd\fR to create such a
708 default route when IPCP comes up, and delete it when the link is
711 In some cases it is desirable to use proxy ARP, for example on a
712 server machine connected to a LAN, in order to allow other hosts to
713 communicate with the remote host. The \fBproxyarp\fR option causes \fIpppd\fR
714 to look for a network interface on the same subnet as the remote host
715 (an interface supporting broadcast and ARP, which is up and not a
716 point-to-point or loopback interface). If found, \fIpppd\fR creates a
717 permanent, published ARP entry with the IP address of the remote host
718 and the hardware address of the network interface found.
721 In the simplest case, you can connect the serial ports of two machines
722 and issue a command like
724 pppd /dev/ttya 9600 passive
726 to each machine, assuming there is no \fIgetty\fR running on the
727 serial ports. If one machine has a \fIgetty\fR running, you can use
728 \fIkermit\fR or \fItip\fR on the other machine to log in to the first
729 machine and issue a command like
733 Then exit from the communications program (making sure the connection
734 isn't dropped), and issue a command like
738 The process of logging in to the other machine and starting \fIpppd\fR
739 can be automated by using the \fBconnect\fR option to run \fIchat\fR,
742 pppd /dev/ttya 38400 connect 'chat "" "" "login:" "username"
743 "Password:" "password" "% " "exec pppd passive"'
745 (Note however that running chat like this will leave the password
746 visible in the parameter list of pppd and chat.)
748 If your serial connection is any more complicated than a piece of
749 wire, you may need to arrange for some control characters to be
750 escaped. In particular, it is often useful to escape XON (^Q) and
751 XOFF (^S), using \fBasyncmap a0000\fR. If the path includes a telnet,
752 you probably should escape ^] as well (\fBasyncmap 200a0000\fR).
753 If the path includes an rlogin, you will need to use the \fBescape
754 ff\fR option on the end which is running the rlogin client, since many
755 rlogin implementations are not
756 transparent; they will remove the sequence [0xff, 0xff, 0x73, 0x73,
757 followed by any 8 bytes] from the stream.
760 Messages are sent to the syslog daemon using facility LOG_DAEMON.
761 (This can be overriden by recompiling \fIpppd\fR with the macro
762 LOG_PPP defined as the desired facility.) In order to see the error
763 and debug messages, you will need to edit your /etc/syslog.conf file
764 to direct the messages to the desired output device or file.
766 The \fBdebug\fR option causes the contents of all control packets sent
767 or received to be logged, that is, all LCP, PAP, CHAP or IPCP packets.
768 This can be useful if the PPP negotiation does not succeed.
769 If debugging is enabled at compile time, the \fBdebug\fR option also
770 causes other debugging messages to be logged.
772 Debugging can also be enabled or disabled by sending a
775 process. This signal acts as a toggle.
778 .B /var/run/ppp\fIn\fB.pid \fR(BSD or Linux), \fB/etc/ppp/ppp\fIn\fB.pid \fR(others)
779 Process-ID for \fIpppd\fR process on ppp interface unit \fIn\fR.
782 A program or script which is executed when the link is available for
783 sending and receiving IP packets (that is, IPCP has come up). It is
784 executed with the parameters
786 \fIinterface-name tty-device speed local-IP-address
789 and with its standard input,
790 output and error streams redirected to \fB/dev/null\fR.
792 This program or script is executed with the same real and effective
793 user-ID as \fIpppd\fR, that is, at least the effective user-ID and
794 possibly the real user-ID will be \fBroot\fR. This is so that it can
795 be used to manipulate routes, run privileged daemons (e.g.
796 \fBsendmail\fR), etc. Be careful that the contents of the
797 /etc/ppp/ip-up and /etc/ppp/ip-down scripts do not compromise your
801 A program or script which is executed when the link is no longer
802 available for sending and receiving IP packets. This script can be
803 used for undoing the effects of the /etc/ppp/ip-up script. It is
804 invoked with the same parameters as the ip-up script, and the same
805 security considerations apply, since it is executed with the same
806 effective and real user-IDs as \fIpppd\fR.
809 A program or script which is executed when the link is available for
810 sending and receiving IPX packets (that is, IPXCP has come up). It is
811 executed with the parameters
813 \fIinterface-name tty-device speed network-number local-IPX-node-address
814 remote-IPX-node-address local-IPX-routing-protocol remote-IPX-routing-protocol
815 local-IPX-router-name remote-IPX-router-name ipparam pppd-pid\fR
817 and with its standard input,
818 output and error streams redirected to \fB/dev/null\fR.
821 The local-IPX-routing-protocol and remote-IPX-routing-protocol field
822 may be one of the following:
824 NONE to indicate that there is no routing protocol
826 RIP to indicate that RIP/SAP should be used
828 NLSP to indicate that Novell NLSP should be used
830 RIP NLSP to indicate that both RIP/SAP and NLSP should be used
833 This program or script is executed with the same real and effective
834 user-ID as \fIpppd\fR, that is, at least the effective user-ID and
835 possibly the real user-ID will be \fBroot\fR. This is so that it can
836 be used to manipulate routes, run privileged daemons (e.g.
837 \fBripd\fR), etc. Be careful that the contents of the
838 /etc/ppp/ipx-up and /etc/ppp/ipx-down scripts do not compromise your
842 A program or script which is executed when the link is no longer
843 available for sending and receiving IPX packets. This script can be
844 used for undoing the effects of the /etc/ppp/ipx-up script. It is
845 invoked with the same parameters as the ipx-up script, and the same
846 security considerations apply, since it is executed with the same
847 effective and real user-IDs as \fIpppd\fR.
849 .B /etc/ppp/pap-secrets
850 Usernames, passwords and IP addresses for PAP authentication.
852 .B /etc/ppp/chap-secrets
853 Names, secrets and IP addresses for CHAP authentication.
856 System default options for
858 read before user default options or command-line options.
861 User default options, read before command-line options.
863 .B /etc/ppp/options.\fIttyname
864 System default options for the serial port being used, read after
865 command-line options.
870 .I Compressing TCP/IP headers for low-speed serial links.
875 .I The MD5 Message-Digest Algorithm.
880 .I PPP Internet Protocol Control Protocol (IPCP).
884 Lloyd, B.; Simpson, W.A.
885 .I PPP authentication protocols.
890 .I The Point\-to\-Point Protocol (PPP).
895 .I PPP in HDLC Framing.
898 The following signals have the specified effect when sent to the
903 These signals cause \fBpppd\fR to terminate the link (by closing LCP),
904 restore the serial device settings, and exit.
907 This signal causes \fBpppd\fR to terminate the link, restore the
908 serial device settings, and close the serial device. If the
909 \fBpersist\fR option has been specified, \fBpppd\fR will try to reopen
910 the serial device and start another connection. Otherwise \fBpppd\fR
916 to renegotiate compression. This can be useful to re-enable
917 compression after it has been disabled as a result of a fatal
918 decompression error. With the BSD Compress scheme, fatal
919 decompression errors generally indicate a bug in one or other
928 Paul Mackerras (paulus@cs.anu.edu.au).