1 .\" manual page [] for pppd 2.3
2 .\" $Id: pppd.8,v 1.51 1999/12/23 01:29:11 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.
30 Pppd provides the basic LCP, authentication support, and an NCP for
31 establishing and configuring the Internet Protocol (IP) (called the IP
32 Control Protocol, IPCP).
33 .SH FREQUENTLY USED OPTIONS
36 Communicate over the named device. The string "/dev/" is prepended if
37 necessary. If no device name is given, or if the name of the terminal
38 connected to the standard input is given, pppd will use that terminal,
39 and will not fork to put itself in the background. A value for this
40 option from a privileged source cannot be overridden by a
44 Set the baud rate to <speed> (a decimal number). On systems such as
45 4.4BSD and NetBSD, any speed can be specified. Other systems
46 (e.g. SunOS) allow only a limited set of speeds.
49 Set the async character map to <map>. This map describes which
50 control characters cannot be successfully received over the serial
51 line. Pppd will ask the peer to send these characters as a 2-byte
52 escape sequence. The argument is a 32 bit hex number with each bit
53 representing a character to escape. Bit 0 (00000001) represents the
54 character 0x00; bit 31 (80000000) represents the character 0x1f or ^_.
55 If multiple \fIasyncmap\fR options are given, the values are ORed
56 together. If no \fIasyncmap\fR option is given, no async character
57 map will be negotiated for the receive direction; the peer should then
58 escape \fIall\fR control characters. To escape transmitted
59 characters, use the \fIescape\fR option.
62 Require the peer to authenticate itself before allowing network
63 packets to be sent or received. This option is the default if the
64 system has a default route. If neither this option nor the
65 \fInoauth\fR option is specified, pppd will only allow the peer to use
66 IP addresses to which the system does not already have a route.
69 Read options from the file /etc/ppp/peers/\fIname\fR. This file may
70 contain privileged options, such as \fInoauth\fR, even if pppd
71 is not being run by root. The \fIname\fR string may not begin with /
72 or include .. as a pathname component. The format of the options file
76 Use the executable or shell command specified by \fIscript\fR to set
77 up the serial line. This script would typically use the chat(8)
78 program to dial the modem and start the remote ppp session. A value
79 for this option from a privileged source cannot be overridden by a
83 Use hardware flow control (i.e. RTS/CTS) to control the flow of
84 data on the serial port. If neither the \fIcrtscts\fR, the
85 \fInocrtscts\fR, the \fIcdtrcts\fR nor the \fInocdtrcts\fR option
86 is given, the hardware flow control setting for the serial port is
88 Some serial ports (such as Macintosh serial ports) lack a true
89 RTS output. Such serial ports use this mode to implement
90 unidirectional flow control. The serial port will
91 suspend transmission when requested by the modem (via CTS)
92 but will be unable to request the modem stop sending to the
93 computer. This mode retains the ability to use DTR as
97 Add a default route to the system routing tables, using the peer as
98 the gateway, when IPCP negotiation is successfully completed.
99 This entry is removed when the PPP connection is broken. This option
100 is privileged if the \fInodefaultroute\fR option has been specified.
102 .B disconnect \fIscript
103 Run the executable or shell command specified by \fIscript\fR after
104 pppd has terminated the link. This script could, for example, issue
105 commands to the modem to cause it to hang up if hardware modem control
106 signals were not available. The disconnect script is not run if the
107 modem has already hung up. A value for this option from a privileged
108 source cannot be overridden by a non-privileged user.
110 .B escape \fIxx,yy,...
111 Specifies that certain characters should be escaped on transmission
112 (regardless of whether the peer requests them to be escaped with its
113 async control character map). The characters to be escaped are
114 specified as a list of hex numbers separated by commas. Note that
115 almost any character can be specified for the \fIescape\fR option,
116 unlike the \fIasyncmap\fR option which only allows control characters
117 to be specified. The characters which may not be escaped are those
118 with hex values 0x20 - 0x3f or 0x5e.
121 Read options from file \fIname\fR (the format is described below).
122 The file must be readable by the user who has invoked pppd.
125 Run the executable or shell command specified by \fIscript\fR to
126 initialize the serial line. This script would typically use the
127 chat(8) program to configure the modem to enable auto answer. A value
128 for this option from a privileged source cannot be overridden by a
132 Specifies that pppd should create a UUCP-style lock file for the
133 serial device to ensure exclusive access to the device.
136 Set the MRU [Maximum Receive Unit] value to \fIn\fR. Pppd
137 will ask the peer to send packets of no more than \fIn\fR bytes. The
138 minimum MRU value is 128. The default MRU value is 1500. A value of
139 296 is recommended for slow links (40 bytes for TCP/IP header + 256
140 bytes of data). (Note that for IPv6 MRU must be at least 1280)
143 Set the MTU [Maximum Transmit Unit] value to \fIn\fR. Unless the
144 peer requests a smaller value via MRU negotiation, pppd will
145 request that the kernel networking code send data packets of no more
146 than \fIn\fR bytes through the PPP network interface. (Note that for
147 IPv6 MTU must be at least 1280)
150 Enables the "passive" option in the LCP. With this option, pppd will
151 attempt to initiate a connection; if no reply is received from the
152 peer, pppd will then just wait passively for a valid LCP packet from
153 the peer, instead of exiting, as it would without this option.
156 .I <local_IP_address>\fB:\fI<remote_IP_address>
157 Set the local and/or remote interface IP addresses. Either one may be
158 omitted. The IP addresses can be specified with a host name or in
159 decimal dot notation (e.g. 150.234.56.78). The default local
160 address is the (first) IP address of the system (unless the
162 option is given). The remote address will be obtained from the peer
163 if not specified in any option. Thus, in simple cases, this option is
164 not required. If a local and/or remote IP address is specified with
166 will not accept a different value from the peer in the IPCP
167 negotiation, unless the \fIipcp-accept-local\fR and/or
168 \fIipcp-accept-remote\fR options are given, respectively.
170 .B ipv6 \fI<local_interface_identifier>\fR,\fI<remote_interface_identifier>
171 Set the local and/or remote 64-bit interface identifier. Either one may be
172 omitted. The identifier must be specified in standard ascii notation of
173 IPv6 addresses (e.g. ::dead:beef). If the
174 \fIipv6cp-use-ipaddr\fR
175 option is given, the local identifier is the local IPv4 address (see above).
176 On systems which supports a unique persistent id, such as EUI-48 derived
177 from the Ethernet MAC address, \fIipv6cp-use-persistent\fR option can be
178 used to replace the \fIipv6 <local>,<remote>\fR option. Otherwise the
179 identifier is randomized.
181 .B active-filter \fIfilter-expression
182 Specifies a packet filter to be applied to data packets to determine
183 which packets are to be regarded as link activity, and therefore reset
184 the idle timer, or cause the link to be brought up in demand-dialling
185 mode. This option is useful in conjunction with the
186 \fBidle\fR option if there are packets being sent or received
187 regularly over the link (for example, routing information packets)
188 which would otherwise prevent the link from ever appearing to be idle.
189 The \fIfilter-expression\fR syntax is as described for tcpdump(1),
190 except that qualifiers which are inappropriate for a PPP link, such as
191 \fBether\fR and \fBarp\fR, are not permitted. Generally the filter
192 expression should be enclosed in single-quotes to prevent whitespace
193 in the expression from being interpreted by the shell. This option
194 is currently only available under NetBSD, and then only
195 if both the kernel and pppd were compiled with PPP_FILTER defined.
197 .B allow-ip \fIaddress(es)
198 Allow peers to use the given IP address or subnet without
199 authenticating themselves. The parameter is parsed as for each
200 element of the list of allowed IP addresses in the secrets files (see
201 the AUTHENTICATION section below).
204 Request that the peer compress packets that it sends, using the
205 BSD-Compress scheme, with a maximum code size of \fInr\fR bits, and
206 agree to compress packets sent to the peer with a maximum code size of
207 \fInt\fR bits. If \fInt\fR is not specified, it defaults to the value
208 given for \fInr\fR. Values in the range 9 to 15 may be used for
209 \fInr\fR and \fInt\fR; larger values give better compression but
210 consume more kernel memory for compression dictionaries.
211 Alternatively, a value of 0 for \fInr\fR or \fInt\fR disables
212 compression in the corresponding direction. Use \fInobsdcomp\fR or
213 \fIbsdcomp 0\fR to disable BSD-Compress compression entirely.
216 Use a non-standard hardware flow control (i.e. DTR/CTS) to control
217 the flow of data on the serial port. If neither the \fIcrtscts\fR,
218 the \fInocrtscts\fR, the \fIcdtrcts\fR nor the \fInocdtrcts\fR
219 option is given, the hardware flow control setting for the serial
220 port is left unchanged.
221 Some serial ports (such as Macintosh serial ports) lack a true
222 RTS output. Such serial ports use this mode to implement true
223 bi-directional flow control. The sacrifice is that this flow
224 control mode does not permit using DTR as a modem control line.
226 .B chap-interval \fIn
227 If this option is given, pppd will rechallenge the peer every \fIn\fR
230 .B chap-max-challenge \fIn
231 Set the maximum number of CHAP challenge transmissions to \fIn\fR
235 Set the CHAP restart interval (retransmission timeout for challenges)
236 to \fIn\fR seconds (default 3).
238 .B connect-delay \fIn
239 Wait for up \fIn\fR milliseconds after the connect script finishes for
240 a valid PPP packet from the peer. At the end of this time, or when a
241 valid PPP packet is received from the peer, pppd will commence
242 negotiation by sending its first LCP packet. The default value is
243 1000 (1 second). This wait period only applies if the \fBconnect\fR
244 or \fBpty\fR option is used.
247 Enables connection debugging facilities.
248 If this option is given, pppd will log the contents of all
249 control packets sent or received in a readable form. The packets are
250 logged through syslog with facility \fIdaemon\fR and level
251 \fIdebug\fR. This information can be directed to a file by setting up
252 /etc/syslog.conf appropriately (see syslog.conf(5)).
255 Disable asyncmap negotiation, forcing all control characters to be
256 escaped for both the transmit and the receive direction.
259 Disable MRU [Maximum Receive Unit] negotiation. With this option,
260 pppd will use the default MRU value of 1500 bytes for both the
261 transmit and receive direction.
264 Request that the peer compress packets that it sends, using the
265 Deflate scheme, with a maximum window size of \fI2**nr\fR bytes, and
266 agree to compress packets sent to the peer with a maximum window size
267 of \fI2**nt\fR bytes. If \fInt\fR is not specified, it defaults to
268 the value given for \fInr\fR. Values in the range 8 to 15 may be used
269 for \fInr\fR and \fInt\fR; larger values give better compression but
270 consume more kernel memory for compression dictionaries.
271 Alternatively, a value of 0 for \fInr\fR or \fInt\fR disables
272 compression in the corresponding direction. Use \fInodeflate\fR or
273 \fIdeflate 0\fR to disable Deflate compression entirely. (Note: pppd
274 requests Deflate compression in preference to BSD-Compress if the peer
278 Initiate the link only on demand, i.e. when data traffic is present.
279 With this option, the remote IP address must be specified by the user
280 on the command line or in an options file. Pppd will initially
281 configure the interface and enable it for IP traffic without
282 connecting to the peer. When traffic is available, pppd will
283 connect to the peer and perform negotiation, authentication, etc.
284 When this is completed, pppd will commence passing data packets
285 (i.e., IP packets) across the link.
287 The \fIdemand\fR option implies the \fIpersist\fR option. If this
288 behaviour is not desired, use the \fInopersist\fR option after the
289 \fIdemand\fR option. The \fIidle\fR and \fIholdoff\fR
290 options are also useful in conjuction with the \fIdemand\fR option.
293 Append the domain name \fId\fR to the local host name for authentication
294 purposes. For example, if gethostname() returns the name porsche, but
295 the fully qualified domain name is porsche.Quotron.COM, you could
296 specify \fIdomain Quotron.COM\fR. Pppd would then use the name
297 \fIporsche.Quotron.COM\fR for looking up secrets in the secrets file,
298 and as the default name to send to the peer when authenticating itself
299 to the peer. This option is privileged.
302 When logging the contents of PAP packets, this option causes pppd to
303 exclude the password string from the log. This is the default.
306 Specifies how many seconds to wait before re-initiating the link after
307 it terminates. This option only has any effect if the \fIpersist\fR
308 or \fIdemand\fR option is used. The holdoff period is not applied if
309 the link was terminated because it was idle.
312 Specifies that pppd should disconnect if the link is idle for \fIn\fR
313 seconds. The link is idle when no data packets (i.e. IP packets) are
314 being sent or received. Note: it is not advisable to use this option
315 with the \fIpersist\fR option without the \fIdemand\fR option.
316 If the \fBactive-filter\fR
317 option is given, data packets which are rejected by the specified
318 activity filter also count as the link being idle.
321 With this option, pppd will accept the peer's idea of our local IP
322 address, even if the local IP address was specified in an option.
324 .B ipcp-accept-remote
325 With this option, pppd will accept the peer's idea of its (remote) IP
326 address, even if the remote IP address was specified in an option.
328 .B ipcp-max-configure \fIn
329 Set the maximum number of IPCP configure-request transmissions to
330 \fIn\fR (default 10).
332 .B ipcp-max-failure \fIn
333 Set the maximum number of IPCP configure-NAKs returned before starting
334 to send configure-Rejects instead to \fIn\fR (default 10).
336 .B ipcp-max-terminate \fIn
337 Set the maximum number of IPCP terminate-request transmissions to
341 Set the IPCP restart interval (retransmission timeout) to \fIn\fR
345 Provides an extra parameter to the ip-up and ip-down scripts. If this
346 option is given, the \fIstring\fR supplied is given as the 6th
347 parameter to those scripts.
349 .B ipv6cp-max-configure \fIn
350 Set the maximum number of IPv6CP configure-request transmissions to
351 \fIn\fR (default 10).
353 .B ipv6cp-max-failure \fIn
354 Set the maximum number of IPv6CP configure-NAKs returned before starting
355 to send configure-Rejects instead to \fIn\fR (default 10).
357 .B ipv6cp-max-terminate \fIn
358 Set the maximum number of IPv6CP terminate-request transmissions to
361 .B ipv6cp-restart \fIn
362 Set the IPv6CP restart interval (retransmission timeout) to \fIn\fR
366 Enable the IPXCP and IPX protocols. This option is presently only
367 supported under Linux, and only if your kernel has been configured to
371 Set the IPX network number in the IPXCP configure request frame to
372 \fIn\fR, a hexadecimal number (without a leading 0x). There is no
373 valid default. If this option is not specified, the network number is
374 obtained from the peer. If the peer does not have the network number,
375 the IPX protocol will not be started.
377 .B ipx-node \fIn\fB:\fIm
378 Set the IPX node numbers. The two node numbers are separated from each
379 other with a colon character. The first number \fIn\fR is the local
380 node number. The second number \fIm\fR is the peer's node number. Each
381 node number is a hexadecimal number, at most 10 digits long. The node
382 numbers on the ipx-network must be unique. There is no valid
383 default. If this option is not specified then the node numbers are
384 obtained from the peer.
386 .B ipx-router-name \fI<string>
387 Set the name of the router. This is a string and is sent to the peer
391 Set the routing protocol to be received by this option. More than one
392 instance of \fIipx-routing\fR may be specified. The '\fInone\fR'
393 option (0) may be specified as the only instance of ipx-routing. The
394 values may be \fI0\fR for \fINONE\fR, \fI2\fR for \fIRIP/SAP\fR, and
395 \fI4\fR for \fINLSP\fR.
397 .B ipxcp-accept-local
398 Accept the peer's NAK for the node number specified in the ipx-node
399 option. If a node number was specified, and non-zero, the default is
400 to insist that the value be used. If you include this option then you
401 will permit the peer to override the entry of the node number.
403 .B ipxcp-accept-network
404 Accept the peer's NAK for the network number specified in the
405 ipx-network option. If a network number was specified, and non-zero, the
406 default is to insist that the value be used. If you include this
407 option then you will permit the peer to override the entry of the node
410 .B ipxcp-accept-remote
411 Use the peer's network number specified in the configure request
412 frame. If a node number was specified for the peer and this option was
413 not specified, the peer will be forced to use the value which you have
416 .B ipxcp-max-configure \fIn
417 Set the maximum number of IPXCP configure request frames which the
418 system will send to \fIn\fR. The default is 10.
420 .B ipxcp-max-failure \fIn
421 Set the maximum number of IPXCP NAK frames which the local system will
422 send before it rejects the options. The default value is 3.
424 .B ipxcp-max-terminate \fIn
425 Set the maximum nuber of IPXCP terminate request frames before the
426 local system considers that the peer is not listening to them. The
430 Enable debugging code in the kernel-level PPP driver. The argument
431 \fIn\fR is a number which is the sum of the following values: 1 to
432 enable general debug messages, 2 to request that the contents of
433 received packets be printed, and 4 to request that the contents of
434 transmitted packets be printed. On most systems, messages printed by
435 the kernel are logged by syslog(1) to a file as directed in the
436 /etc/syslog.conf configuration file.
439 Enables pppd to alter kernel settings as appropriate. Under Linux,
440 pppd will enable IP forwarding (i.e. set /proc/sys/net/ipv4/ip_forward
441 to 1) if the \fIproxyarp\fR option is used, and will enable the
442 dynamic IP address option (i.e. set /proc/sys/net/ipv4/ip_dynaddr to
443 1) in demand mode if the local address changes.
445 .B lcp-echo-failure \fIn
446 If this option is given, pppd will presume the peer to be dead
447 if \fIn\fR LCP echo-requests are sent without receiving a valid LCP
448 echo-reply. If this happens, pppd will terminate the
449 connection. Use of this option requires a non-zero value for the
450 \fIlcp-echo-interval\fR parameter. This option can be used to enable
451 pppd to terminate after the physical connection has been broken
452 (e.g., the modem has hung up) in situations where no hardware modem
453 control lines are available.
455 .B lcp-echo-interval \fIn
456 If this option is given, pppd will send an LCP echo-request frame to
457 the peer every \fIn\fR seconds. Normally the peer should respond to
458 the echo-request by sending an echo-reply. This option can be used
459 with the \fIlcp-echo-failure\fR option to detect that the peer is no
462 .B lcp-max-configure \fIn
463 Set the maximum number of LCP configure-request transmissions to
464 \fIn\fR (default 10).
466 .B lcp-max-failure \fIn
467 Set the maximum number of LCP configure-NAKs returned before starting
468 to send configure-Rejects instead to \fIn\fR (default 10).
470 .B lcp-max-terminate \fIn
471 Set the maximum number of LCP terminate-request transmissions to
475 Set the LCP restart interval (retransmission timeout) to \fIn\fR
478 .B linkname \fIname\fR
479 Sets the logical name of the link to \fIname\fR. Pppd will create a
480 file named \fBppp-\fIname\fB.pid\fR in /var/run (or /etc/ppp on some
481 systems) containing its process ID. This can be useful in determining
482 which instance of pppd is responsible for the link to a given peer
483 system. This is a privileged option.
486 Don't use the modem control lines. With this option, pppd will ignore
487 the state of the CD (Carrier Detect) signal from the modem and will
488 not change the state of the DTR (Data Terminal Ready) signal.
491 Send log messages to file descriptor \fIn\fR. Pppd will send log
492 messages to at most one file or file descriptor (as well as sending
493 the log messages to syslog), so this option and the \fBlogfile\fR
494 option are mutually exclusive. The default is for pppd to send log
495 messages to stdout (file descriptor 1), unless the serial port is
496 already open on stdout.
498 .B logfile \fIfilename
499 Append log messages to the file \fIfilename\fR (as well as sending the
500 log messages to syslog). The file is opened with the privileges of
501 the user who invoked pppd, in append mode.
504 Use the system password database for authenticating the peer using
505 PAP, and record the user in the system wtmp file. Note that the peer
506 must have an entry in the /etc/ppp/pap-secrets file as well as the
507 system password database to be allowed access.
510 Terminate the connection when it has been available for network
511 traffic for \fIn\fR seconds (i.e. \fIn\fR seconds after the first
512 network control protocol comes up).
515 Terminate after \fIn\fR consecutive failed connection attempts. A
516 value of 0 means no limit. The default value is 10.
519 Use the modem control lines. This option is the default. With this
520 option, pppd will wait for the CD (Carrier Detect) signal from the
521 modem to be asserted when opening the serial device (unless a connect
522 script is specified), and it will drop the DTR (Data Terminal Ready)
523 signal briefly when the connection is terminated and before executing
524 the connect script. On Ultrix, this option implies hardware flow
525 control, as for the \fIcrtscts\fR option.
528 If pppd is acting as a server for Microsoft Windows clients, this
529 option allows pppd to supply one or two DNS (Domain Name Server)
530 addresses to the clients. The first instance of this option specifies
531 the primary DNS address; the second instance (if given) specifies the
532 secondary DNS address. (This option was present in some older
533 versions of pppd under the name \fBdns-addr\fR.)
536 If pppd is acting as a server for Microsoft Windows or "Samba"
537 clients, this option allows pppd to supply one or two WINS (Windows
538 Internet Name Services) server addresses to the clients. The first
539 instance of this option specifies the primary WINS address; the second
540 instance (if given) specifies the secondary WINS address.
543 Set the name of the local system for authentication purposes to
544 \fIname\fR. This is a privileged option. With this option, pppd will
545 use lines in the secrets files which have \fIname\fR as the second
546 field when looking for a secret to use in authenticating the peer. In
547 addition, unless overridden with the \fIuser\fR option, \fIname\fR
548 will be used as the name to send to the peer when authenticating the
549 local system to the peer. (Note that pppd does not append the domain
553 Set the interface netmask to \fIn\fR, a 32 bit netmask in "decimal dot"
554 notation (e.g. 255.255.255.0). If this option is given, the value
555 specified is ORed with the default netmask. The default netmask is
556 chosen based on the negotiated remote IP address; it is the
557 appropriate network mask for the class of the remote IP address, ORed
558 with the netmasks for any non point-to-point network interfaces in the
559 system which are on the same network. (Note: on some platforms, pppd
560 will always use 255.255.255.255 for the netmask, if that is the only
561 appropriate value for a point-to-point interface.)
564 Disable Address/Control compression in both directions (send and
568 Do not require the peer to authenticate itself. This option is
572 Disables BSD-Compress compression; \fBpppd\fR will not request or
573 agree to compress packets using the BSD-Compress scheme.
576 Disable CCP (Compression Control Protocol) negotiation. This option
577 should only be required if the peer is buggy and gets confused by
578 requests from pppd for CCP negotiation.
581 Disable hardware flow control (i.e. RTS/CTS) on the serial port.
582 If neither the \fIcrtscts\fR nor the \fInocrtscts\fR nor the
583 \fIcdtrcts\fR nor the \fInodtrcts\fR option is given, the hardware
584 flow control setting for the serial port is left unchanged.
587 This option is a synonym for \fInocrtscts\fR. Either of these options will
588 disable both forms of hardware flow control.
591 Disable the \fIdefaultroute\fR option. The system administrator who
592 wishes to prevent users from creating default routes with pppd
593 can do so by placing this option in the /etc/ppp/options file.
596 Disables Deflate compression; pppd will not request or agree to
597 compress packets using the Deflate scheme.
600 Don't detach from the controlling terminal. Without this option, if a
601 serial device other than the terminal on the standard input is
602 specified, pppd will fork to become a background process.
605 Disable IPCP negotiation and IP communication. This option should
606 only be required if the peer is buggy and gets confused by requests
607 from pppd for IPCP negotiation.
610 Disable IPv6CP negotiation and IPv6 communication. This option should
611 only be required if the peer is buggy and gets confused by requests
612 from pppd for IPv6CP negotiation.
615 Disables the default behaviour when no local IP address is specified,
616 which is to determine (if possible) the local IP address from the
617 hostname. With this option, the peer will have to supply the local IP
618 address during IPCP negotiation (unless it specified explicitly on the
619 command line or in an options file).
622 Disable the IPXCP and IPX protocols. This option should only be
623 required if the peer is buggy and gets confused by requests from pppd
624 for IPXCP negotiation.
627 Opposite of the \fIktune\fR option; disables pppd from changing system
631 Do not send log messages to a file or file descriptor. This option
632 cancels the \fBlogfd\fR and \fBlogfile\fR options.
634 Disable magic number negotiation. With this option, pppd cannot
635 detect a looped-back line. This option should only be needed if the
639 Disable protocol field compression negotiation in both the receive and
640 the transmit direction.
643 Exit once a connection has been made and terminated. This is the
644 default unless the \fIpersist\fR or \fIdemand\fR option has been
648 Do not accept or agree to Predictor-1 compression.
651 Disable the \fIproxyarp\fR option. The system administrator who
652 wishes to prevent users from creating proxy ARP entries with pppd can
653 do so by placing this option in the /etc/ppp/options file.
656 Normally, pppd requires a terminal device. With this option, pppd
657 will allocate itself a pseudo-tty master/slave pair and use the slave
658 as its terminal device. Pppd will create a child process to act as a
659 `character shunt' to transfer characters between the pseudo-tty master
660 and its standard input and output. Thus pppd will transmit characters
661 on its standard output and receive characters on its standard input
662 even if they are not terminal devices. This option increases the
663 latency and CPU overhead of transferring data over the ppp interface
664 as all of the characters sent and received must flow through the
665 character shunt process. An explicit device name may not be given if
669 Disable Van Jacobson style TCP/IP header compression in both the
670 transmit and the receive direction.
673 Disable the connection-ID compression option in Van Jacobson style
674 TCP/IP header compression. With this option, pppd will not omit the
675 connection-ID byte from Van Jacobson compressed TCP/IP headers, nor
676 ask the peer to do so.
679 Indicates that all secrets in the /etc/ppp/pap-secrets file which are
680 used for checking the identity of the peer are encrypted, and thus
681 pppd should not accept a password which, before encryption, is
682 identical to the secret from the /etc/ppp/pap-secrets file.
684 .B pap-max-authreq \fIn
685 Set the maximum number of PAP authenticate-request transmissions to
686 \fIn\fR (default 10).
689 Set the PAP restart interval (retransmission timeout) to \fIn\fR
693 Set the maximum time that pppd will wait for the peer to authenticate
694 itself with PAP to \fIn\fR seconds (0 means no limit).
696 .B pass-filter \fIfilter-expression
697 Specifies a packet filter to applied to data packets being sent or
698 received to determine which packets should be allowed to pass.
699 Packets which are rejected by the filter are silently discarded. This
700 option can be used to prevent specific network daemons (such as
701 routed) using up link bandwidth, or to provide a basic firewall
703 The \fIfilter-expression\fR syntax is as described for tcpdump(1),
704 except that qualifiers which are inappropriate for a PPP link, such as
705 \fBether\fR and \fBarp\fR, are not permitted. Generally the filter
706 expression should be enclosed in single-quotes to prevent whitespace
707 in the expression from being interpreted by the shell. Note that it
708 is possible to apply different constraints to incoming and outgoing
709 packets using the \fBinbound\fR and \fBoutbound\fR qualifiers. This
710 option is currently only available under NetBSD, and then only if both
711 the kernel and pppd were compiled with PPP_FILTER defined.
714 Do not exit after a connection is terminated; instead try to reopen
717 .B plugin \fIfilename
718 Load the shared library object file \fIfilename\fR as a plugin. This
719 is a privileged option.
722 Request that the peer compress frames that it sends using Predictor-1
723 compression, and agree to compress transmitted frames with Predictor-1
724 if requested. This option has no effect unless the kernel driver
725 supports Predictor-1 compression.
727 .B privgroup \fIgroup-name
728 Allows members of group \fIgroup-name\fR to use privileged options.
729 This is a privileged option. Use of this option requires care as
730 there is no guarantee that members of \fIgroup-name\fR cannot use pppd
731 to become root themselves. Consider it equivalent to putting the
732 members of \fIgroup-name\fR in the kmem or disk group.
735 Add an entry to this system's ARP [Address Resolution Protocol] table
736 with the IP address of the peer and the Ethernet address of this
737 system. This will have the effect of making the peer appear to other
738 systems to be on the local ethernet.
741 Specifies that the command \fIscript\fR is to be used to communicate
742 rather than a specific terminal device. Pppd will allocate itself a
743 pseudo-tty master/slave pair and use the slave as its terminal
744 device. The \fIscript\fR will be run in a child process with the
745 pseudo-tty master as its standard input and output. An explicit
746 device name may not be given if this option is used. (Note: if the
747 \fIrecord\fR option is used in conjuction with the \fIpty\fR option,
748 the child process will have pipes on its standard input and output.)
751 With this option, pppd will accept all control characters from the
752 peer, including those marked in the receive asyncmap. Without this
753 option, pppd will discard those characters as specified in RFC1662.
754 This option should only be needed if the peer is buggy.
756 .B record \fIfilename
757 Specifies that pppd should record all characters sent and received to
758 a file named \fIfilename\fR. This file is opened in append mode,
759 using the user's user-ID and permissions. This option is implemented
760 using a pseudo-tty and a process to transfer characters between the
761 pseudo-tty and the real serial device, so it will increase the latency
762 and CPU overhead of transferring data over the ppp interface. The
763 characters are stored in a tagged format with timestamps, which can be
764 displayed in readable form using the pppdump(8) program.
766 .B remotename \fIname
767 Set the assumed name of the remote system for authentication purposes
771 With this option, pppd will not agree to authenticate itself to the
775 With this option, pppd will not agree to authenticate itself to the
779 Require the peer to authenticate itself using CHAP [Challenge
780 Handshake Authentication Protocol] authentication.
783 Require the peer to authenticate itself using PAP [Password
784 Authentication Protocol] authentication.
787 When logging the contents of PAP packets, this option causes pppd to
788 show the password string in the log message.
791 With this option, pppd will not transmit LCP packets to initiate a
792 connection until a valid LCP packet is received from the peer (as for
793 the `passive' option with ancient versions of pppd).
796 Use synchronous HDLC serial encoding instead of asynchronous.
797 The device used by pppd with this option must have sync support.
798 Currently supports Microgate SyncLink adapters
799 under Linux and FreeBSD 2.2.8 and later.
802 With this option, pppd will detach from its controlling terminal once
803 it has successfully established the ppp connection (to the point where
804 the first network control protocol, usually the IP control protocol,
808 Enforce the use of the hostname (with domain name appended, if given)
809 as the name of the local system for authentication purposes (overrides
810 the \fIname\fR option). This option is not normally needed since the
811 \fIname\fR option is privileged.
814 Ask the peer for up to 2 DNS server addresses. The addresses supplied
815 by the peer (if any) are passed to the /etc/ppp/ip-up script in the
816 environment variables DNS1 and DNS2. In addition, pppd will create an
817 /etc/ppp/resolv.conf file containing one or two nameserver lines with
818 the address(es) supplied by the peer.
821 Sets the name used for authenticating the local system to the peer to
825 Sets the number of connection slots to be used by the Van Jacobson
826 TCP/IP header compression and decompression code to \fIn\fR, which
827 must be between 2 and 16 (inclusive).
830 Run the executable or shell command specified by \fIscript\fR before
831 initiating PPP negotiation, after the connect script (if any) has
832 completed. A value for this option from a privileged source cannot be
833 overridden by a non-privileged user.
836 Use software flow control (i.e. XON/XOFF) to control the flow of data on
839 Options can be taken from files as well as the command line. Pppd
840 reads options from the files /etc/ppp/options, ~/.ppprc and
841 /etc/ppp/options.\fIttyname\fR (in that order) before processing the
842 options on the command line. (In fact, the command-line options are
843 scanned to find the terminal name before the options.\fIttyname\fR
844 file is read.) In forming the name of the options.\fIttyname\fR file,
845 the initial /dev/ is removed from the terminal name, and any remaining
846 / characters are replaced with dots.
848 An options file is parsed into a series of words, delimited by
849 whitespace. Whitespace can be included in a word by enclosing the
850 word in double-quotes ("). A backslash (\\) quotes the following character.
851 A hash (#) starts a comment, which continues until the end of the
852 line. There is no restriction on using the \fIfile\fR or \fIcall\fR
853 options within an options file.
856 provides system administrators with sufficient access control that PPP
857 access to a server machine can be provided to legitimate users without
858 fear of compromising the security of the server or the network it's
859 on. This control is provided through restrictions on which IP
860 addresses the peer may use, based on its authenticated identity (if
861 any), and through restrictions on which options a non-privileged user
862 may use. Several of pppd's options are privileged, in particular
863 those which permit potentially insecure configurations; these options
864 are only accepted in files which are under the control of the system
865 administrator, or if pppd is being run by root.
867 The default behaviour of pppd is to allow an unauthenticated peer to
868 use a given IP address only if the system does not already have a
869 route to that IP address. For example, a system with a
870 permanent connection to the wider internet will normally have a
871 default route, and thus all peers will have to authenticate themselves
872 in order to set up a connection. On such a system, the \fIauth\fR
873 option is the default. On the other hand, a system where the
874 PPP link is the only connection to the internet will not normally have
875 a default route, so the peer will be able to use almost any IP address
876 without authenticating itself.
878 As indicated above, some security-sensitive options are privileged,
879 which means that they may not be used by an ordinary non-privileged
880 user running a setuid-root pppd, either on the command line, in the
881 user's ~/.ppprc file, or in an options file read using the \fIfile\fR
882 option. Privileged options may be used in /etc/ppp/options file or in
883 an options file read using the \fIcall\fR option. If pppd is being
884 run by the root user, privileged options can be used without
887 When opening the device, pppd uses either the invoking user's user ID
888 or the root UID (that is, 0), depending on whether the device name was
889 specified by the user or the system administrator. If the device name
890 comes from a privileged source, that is, /etc/ppp/options or an
891 options file read using the \fIcall\fR option, pppd uses full root
892 privileges when opening the device. Thus, by creating an appropriate
893 file under /etc/ppp/peers, the system administrator can allow users to
894 establish a ppp connection via a device which they would not normally
895 have permission to access. Otherwise pppd uses the invoking user's
896 real UID when opening the device.
898 Authentication is the process whereby one peer convinces the other of
899 its identity. This involves the first peer sending its name to the
900 other, together with some kind of secret information which could only
901 come from the genuine authorized user of that name. In such an
902 exchange, we will call the first peer the "client" and the other the
903 "server". The client has a name by which it identifies itself to the
904 server, and the server also has a name by which it identifies itself
905 to the client. Generally the genuine client shares some secret (or
906 password) with the server, and authenticates itself by proving that it
907 knows that secret. Very often, the names used for authentication
908 correspond to the internet hostnames of the peers, but this is not
911 At present, pppd supports two authentication protocols: the Password
912 Authentication Protocol (PAP) and the Challenge Handshake
913 Authentication Protocol (CHAP). PAP involves the client sending its
914 name and a cleartext password to the server to authenticate itself.
915 In contrast, the server initiates the CHAP authentication exchange by
916 sending a challenge to the client (the challenge packet includes the
917 server's name). The client must respond with a response which
918 includes its name plus a hash value derived from the shared secret and
919 the challenge, in order to prove that it knows the secret.
921 The PPP protocol, being symmetrical, allows both peers to require the
922 other to authenticate itself. In that case, two separate and
923 independent authentication exchanges will occur. The two exchanges
924 could use different authentication protocols, and in principle,
925 different names could be used in the two exchanges.
927 The default behaviour of pppd is to agree to authenticate if
928 requested, and to not require authentication from the peer. However,
929 pppd will not agree to authenticate itself with a particular protocol
930 if it has no secrets which could be used to do so.
932 Pppd stores secrets for use in authentication in secrets
933 files (/etc/ppp/pap-secrets for PAP, /etc/ppp/chap-secrets for CHAP).
934 Both secrets files have the same format. The secrets files can
935 contain secrets for pppd to use in authenticating itself to other
936 systems, as well as secrets for pppd to use when authenticating other
939 Each line in a secrets file contains one secret. A given secret is
940 specific to a particular combination of client and server - it can
941 only be used by that client to authenticate itself to that server.
942 Thus each line in a secrets file has at least 3 fields: the name of
943 the client, the name of the server, and the secret. These fields may
944 be followed by a list of the IP addresses that the specified client
945 may use when connecting to the specified server.
947 A secrets file is parsed into words as for a options file, so the
948 client name, server name and secrets fields must each be one word,
949 with any embedded spaces or other special characters quoted or
950 escaped. Note that case is significant in the client and server names
953 If the secret starts with an `@', what follows is assumed to be the
954 name of a file from which to read the secret. A "*" as the client or
955 server name matches any name. When selecting a secret, pppd takes the
956 best match, i.e. the match with the fewest wildcards.
958 Any following words on the same line are taken to be a list of
959 acceptable IP addresses for that client. If there are only 3 words on
960 the line, or if the first word is "-", then all IP addresses are
961 disallowed. To allow any address, use "*". A word starting with "!"
962 indicates that the specified address is \fInot\fR acceptable. An
963 address may be followed by "/" and a number \fIn\fR, to indicate a
964 whole subnet, i.e. all addresses which have the same value in the most
965 significant \fIn\fR bits. In this form, the address may be followed
966 by a plus sign ("+") to indicate that one address from the subnet is
967 authorized, based on the ppp network interface unit number in use.
968 In this case, the host part of the address will be set to the unit
971 Thus a secrets file contains both secrets for use in authenticating
972 other hosts, plus secrets which we use for authenticating ourselves to
973 others. When pppd is authenticating the peer (checking the peer's
974 identity), it chooses a secret with the peer's name in the first
975 field and the name of the local system in the second field. The
976 name of the local system defaults to the hostname, with the domain
977 name appended if the \fIdomain\fR option is used. This default can be
978 overridden with the \fIname\fR option, except when the
979 \fIusehostname\fR option is used.
981 When pppd is choosing a secret to use in authenticating itself to the
982 peer, it first determines what name it is going to use to identify
983 itself to the peer. This name can be specified by the user with the
984 \fIuser\fR option. If this option is not used, the name defaults to
985 the name of the local system, determined as described in the previous
986 paragraph. Then pppd looks for a secret with this name in the first
987 field and the peer's name in the second field. Pppd will know the
988 name of the peer if CHAP authentication is being used, because the
989 peer will have sent it in the challenge packet. However, if PAP is being
990 used, pppd will have to determine the peer's name from the options
991 specified by the user. The user can specify the peer's name directly
992 with the \fIremotename\fR option. Otherwise, if the remote IP address
993 was specified by a name (rather than in numeric form), that name will
994 be used as the peer's name. Failing that, pppd will use the null
995 string as the peer's name.
997 When authenticating the peer with PAP, the supplied password is first
998 compared with the secret from the secrets file. If the password
999 doesn't match the secret, the password is encrypted using crypt() and
1000 checked against the secret again. Thus secrets for authenticating the
1001 peer can be stored in encrypted form if desired. If the
1002 \fIpapcrypt\fR option is given, the first (unencrypted) comparison is
1003 omitted, for better security.
1005 Furthermore, if the \fIlogin\fR option was specified, the username and
1006 password are also checked against the system password database. Thus,
1007 the system administrator can set up the pap-secrets file to allow PPP
1008 access only to certain users, and to restrict the set of IP addresses
1009 that each user can use. Typically, when using the \fIlogin\fR option,
1010 the secret in /etc/ppp/pap-secrets would be "", which will match any
1011 password supplied by the peer. This avoids the need to have the same
1012 secret in two places.
1014 Authentication must be satisfactorily completed before IPCP (or any
1015 other Network Control Protocol) can be started. If the peer is
1016 required to authenticate itself, and fails to do so, pppd will
1017 terminated the link (by closing LCP). If IPCP negotiates an
1018 unacceptable IP address for the remote host, IPCP will be closed. IP
1019 packets can only be sent or received when IPCP is open.
1021 In some cases it is desirable to allow some hosts which can't
1022 authenticate themselves to connect and use one of a restricted set of
1023 IP addresses, even when the local host generally requires
1024 authentication. If the peer refuses to authenticate itself when
1025 requested, pppd takes that as equivalent to authenticating with PAP
1026 using the empty string for the username and password. Thus, by adding
1027 a line to the pap-secrets file which specifies the empty string for
1028 the client and password, it is possible to allow restricted access to
1029 hosts which refuse to authenticate themselves.
1032 When IPCP negotiation is completed successfully, pppd will inform the
1033 kernel of the local and remote IP addresses for the ppp interface.
1034 This is sufficient to create a host route to the remote end of the
1035 link, which will enable the peers to exchange IP packets.
1036 Communication with other machines generally requires further
1037 modification to routing tables and/or ARP (Address Resolution
1038 Protocol) tables. In most cases the \fIdefaultroute\fR and/or
1039 \fIproxyarp\fR options are sufficient for this, but in some cases
1040 further intervention is required. The /etc/ppp/ip-up script can be
1043 Sometimes it is desirable to add a default route through the remote
1044 host, as in the case of a machine whose only connection to the
1045 Internet is through the ppp interface. The \fIdefaultroute\fR option
1046 causes pppd to create such a default route when IPCP comes up, and
1047 delete it when the link is terminated.
1049 In some cases it is desirable to use proxy ARP, for example on a
1050 server machine connected to a LAN, in order to allow other hosts to
1051 communicate with the remote host. The \fIproxyarp\fR option causes
1052 pppd to look for a network interface on the same subnet as the remote
1053 host (an interface supporting broadcast and ARP, which is up and not a
1054 point-to-point or loopback interface). If found, pppd creates a
1055 permanent, published ARP entry with the IP address of the remote host
1056 and the hardware address of the network interface found.
1058 When the \fIdemand\fR option is used, the interface IP addresses have
1059 already been set at the point when IPCP comes up. If pppd has not
1060 been able to negotiate the same addresses that it used to configure
1061 the interface (for example when the peer is an ISP that uses dynamic
1062 IP address assignment), pppd has to change the interface IP addresses
1063 to the negotiated addresses. This may disrupt existing connections,
1064 and the use of demand dialling with peers that do dynamic IP address
1065 assignment is not recommended.
1068 The following examples assume that the /etc/ppp/options file contains
1069 the \fIauth\fR option (as in the default /etc/ppp/options file in the
1072 Probably the most common use of pppd is to dial out to an ISP. This
1073 can be done with a command such as
1077 where the /etc/ppp/peers/isp file is set up by the system
1078 administrator to contain something like this:
1082 connect '/usr/sbin/chat -v -f /etc/ppp/chat-isp'
1086 In this example, we are using chat to dial the ISP's modem and go
1087 through any logon sequence required. The /etc/ppp/chat-isp file
1088 contains the script used by chat; it could for example contain
1089 something like this:
1101 ABORT "Username/Password Incorrect"
1109 "name:" "^Umyuserid"
1111 "word:" "\\qmypassword"
1117 See the chat(8) man page for details of chat scripts.
1119 Pppd can also be used to provide a dial-in ppp service for users. If
1120 the users already have login accounts, the simplest way to set up the
1121 ppp service is to let the users log in to their accounts and run pppd
1122 (installed setuid-root) with a command such as
1126 To allow a user to use the PPP facilities, you need to allocate an IP
1127 address for that user's machine and create an entry in
1128 /etc/ppp/pap-secrets or /etc/ppp/chap-secrets (depending on which
1129 authentication method the PPP implementation on the user's machine
1130 supports), so that the user's
1131 machine can authenticate itself. For example, if Joe has a machine
1132 called "joespc" which is to be allowed to dial in to the machine
1133 called "server" and use the IP address joespc.my.net, you would add an
1134 entry like this to /etc/ppp/pap-secrets or /etc/ppp/chap-secrets:
1136 joespc server "joe's secret" joespc.my.net
1138 Alternatively, you can create a username called (for example) "ppp",
1139 whose login shell is pppd and whose home directory is /etc/ppp.
1140 Options to be used when pppd is run this way can be put in
1143 If your serial connection is any more complicated than a piece of
1144 wire, you may need to arrange for some control characters to be
1145 escaped. In particular, it is often useful to escape XON (^Q) and
1146 XOFF (^S), using \fIasyncmap a0000\fR. If the path includes a telnet,
1147 you probably should escape ^] as well (\fIasyncmap 200a0000\fR). If
1148 the path includes an rlogin, you will need to use the \fIescape ff\fR
1149 option on the end which is running the rlogin client, since many
1150 rlogin implementations are not transparent; they will remove the
1151 sequence [0xff, 0xff, 0x73, 0x73, followed by any 8 bytes] from the
1155 Messages are sent to the syslog daemon using facility LOG_DAEMON.
1156 (This can be overriden by recompiling pppd with the macro
1157 LOG_PPP defined as the desired facility.) In order to see the error
1158 and debug messages, you will need to edit your /etc/syslog.conf file
1159 to direct the messages to the desired output device or file.
1161 The \fIdebug\fR option causes the contents of all control packets sent
1162 or received to be logged, that is, all LCP, PAP, CHAP or IPCP packets.
1163 This can be useful if the PPP negotiation does not succeed or if
1164 authentication fails.
1165 If debugging is enabled at compile time, the \fIdebug\fR option also
1166 causes other debugging messages to be logged.
1168 Debugging can also be enabled or disabled by sending a SIGUSR1 signal
1169 to the pppd process. This signal acts as a toggle.
1171 The exit status of pppd is set to indicate whether any error was
1172 detected, or the reason for the link being terminated. The values
1176 Pppd has detached, or otherwise the connection was successfully
1177 established and terminated at the peer's request.
1180 An immediately fatal error of some kind occurred, such as an essential
1181 system call failing, or running out of virtual memory.
1184 An error was detected in processing the options given, such as two
1185 mutually exclusive options being used.
1188 Pppd is not setuid-root and the invoking user is not root.
1191 The kernel does not support PPP, for example, the PPP kernel driver is
1192 not included or cannot be loaded.
1195 Pppd terminated because it was sent a SIGINT, SIGTERM or SIGHUP
1199 The serial port could not be locked.
1202 The serial port could not be opened.
1205 The connect script failed (returned a non-zero exit status).
1208 The command specified as the argument to the \fIpty\fR option could
1212 The PPP negotiation failed, that is, it didn't reach the point where
1213 at least one network protocol (e.g. IP) was running.
1216 The peer system failed (or refused) to authenticate itself.
1219 The link was established successfully and terminated because it was
1223 The link was established successfully and terminated because the
1224 connect time limit was reached.
1227 Callback was negotiated and an incoming call should arrive shortly.
1230 The link was terminated because the peer is not responding to echo
1234 The link was terminated by the modem hanging up.
1237 The PPP negotiation failed because serial loopback was detected.
1240 The init script failed (returned a non-zero exit status).
1243 We failed to authenticate ourselves to the peer.
1245 Pppd invokes scripts at various stages in its processing which can be
1246 used to perform site-specific ancillary processing. These scripts are
1247 usually shell scripts, but could be executable code files instead.
1248 Pppd does not wait for the scripts to finish. The scripts are
1249 executed as root (with the real and effective user-id set to 0), so
1250 that they can do things such as update routing tables or run
1251 privileged daemons. Be careful that the contents of these scripts do
1252 not compromise your system's security. Pppd runs the scripts with
1253 standard input, output and error redirected to /dev/null, and with an
1254 environment that is empty except for some environment variables that
1255 give information about the link. The environment variables that pppd
1259 The name of the serial tty device being used.
1262 The name of the network interface being used.
1265 The IP address for the local end of the link. This is only set when
1269 The IP address for the remote end of the link. This is only set when
1273 The authenticated name of the peer. This is only set if the peer
1274 authenticates itself.
1277 The baud rate of the tty device.
1280 The real user-id of the user who invoked pppd.
1283 The username of the real user-id that invoked pppd. This is always set.
1285 For the ip-down and auth-down scripts, pppd also sets the following
1286 variables giving statistics for the connection:
1289 The number of seconds from when the PPP negotiation started until the
1290 connection was terminated.
1293 The number of bytes sent (at the level of the serial port) during the
1297 The number of bytes received (at the level of the serial port) during
1301 The logical name of the link, set with the \fIlinkname\fR option.
1303 Pppd invokes the following scripts, if they exist. It is not an error
1304 if they don't exist.
1307 A program or script which is executed after the remote system
1308 successfully authenticates itself. It is executed with the parameters
1310 \fIinterface-name peer-name user-name tty-device speed\fR
1312 Note that this script is not executed if the peer doesn't authenticate
1313 itself, for example when the \fInoauth\fR option is used.
1315 .B /etc/ppp/auth-down
1316 A program or script which is executed when the link goes down, if
1317 /etc/ppp/auth-up was previously executed. It is executed in the same
1318 manner with the same parameters as /etc/ppp/auth-up.
1321 A program or script which is executed when the link is available for
1322 sending and receiving IP packets (that is, IPCP has come up). It is
1323 executed with the parameters
1325 \fIinterface-name tty-device speed local-IP-address
1326 remote-IP-address ipparam\fR
1329 A program or script which is executed when the link is no longer
1330 available for sending and receiving IP packets. This script can be
1331 used for undoing the effects of the /etc/ppp/ip-up script. It is
1332 invoked in the same manner and with the same parameters as the ip-up
1336 Like /etc/ppp/ip-up, except that it is executed when the link is available
1337 for sending and receiving IPv6 packets. It is executed with the parameters
1339 \fIinterface-name tty-device speed local-link-local-address
1340 remote-link-local-address ipparam\fR
1342 .B /etc/ppp/ipv6-down
1343 Similar to /etc/ppp/ip-down, but it is executed when IPv6 packets can no
1344 longer be transmitted on the link. It is executed with the same parameters
1345 as the ipv6-up script.
1348 A program or script which is executed when the link is available for
1349 sending and receiving IPX packets (that is, IPXCP has come up). It is
1350 executed with the parameters
1352 \fIinterface-name tty-device speed network-number local-IPX-node-address
1353 remote-IPX-node-address local-IPX-routing-protocol remote-IPX-routing-protocol
1354 local-IPX-router-name remote-IPX-router-name ipparam pppd-pid\fR
1356 The local-IPX-routing-protocol and remote-IPX-routing-protocol field
1357 may be one of the following:
1359 NONE to indicate that there is no routing protocol
1361 RIP to indicate that RIP/SAP should be used
1363 NLSP to indicate that Novell NLSP should be used
1365 RIP NLSP to indicate that both RIP/SAP and NLSP should be used
1367 .B /etc/ppp/ipx-down
1368 A program or script which is executed when the link is no longer
1369 available for sending and receiving IPX packets. This script can be
1370 used for undoing the effects of the /etc/ppp/ipx-up script. It is
1371 invoked in the same manner and with the same parameters as the ipx-up
1375 .B /var/run/ppp\fIn\fB.pid \fR(BSD or Linux), \fB/etc/ppp/ppp\fIn\fB.pid \fR(others)
1376 Process-ID for pppd process on ppp interface unit \fIn\fR.
1378 .B /var/run/ppp-\fIname\fB.pid \fR(BSD or Linux), \fB/etc/ppp/ppp-\fIname\fB.pid \fR(others)
1379 Process-ID for pppd process for logical link \fIname\fR (see the
1380 \fIlinkname\fR option).
1382 .B /etc/ppp/pap-secrets
1383 Usernames, passwords and IP addresses for PAP authentication. This
1384 file should be owned by root and not readable or writable by any other
1385 user. Pppd will log a warning if this is not the case.
1387 .B /etc/ppp/chap-secrets
1388 Names, secrets and IP addresses for CHAP authentication. As for
1389 /etc/ppp/pap-secrets, this file should be owned by root and not
1390 readable or writable by any other user. Pppd will log a warning if
1391 this is not the case.
1394 System default options for pppd, read before user default options or
1395 command-line options.
1398 User default options, read before /etc/ppp/options.\fIttyname\fR.
1400 .B /etc/ppp/options.\fIttyname
1401 System default options for the serial port being used, read after
1402 ~/.ppprc. In forming the \fIttyname\fR part of this
1403 filename, an initial /dev/ is stripped from the port name (if
1404 present), and any slashes in the remaining part are converted to
1408 A directory containing options files which may contain privileged
1409 options, even if pppd was invoked by a user other than root. The
1410 system administrator can create options files in this directory to
1411 permit non-privileged users to dial out without requiring the peer to
1412 authenticate, but only to certain trusted peers.
1417 \fICompressing TCP/IP headers for low-speed serial links.\fR
1422 .I The MD5 Message-Digest Algorithm.
1427 .I PPP Internet Protocol Control Protocol (IPCP).
1431 Lloyd, B.; Simpson, W.A.
1432 .I PPP authentication protocols.
1437 .I The Point\-to\-Point Protocol (PPP).
1442 .I PPP in HDLC-like Framing.
1447 .I IP Version 6 over PPP
1450 The following signals have the specified effect when sent to pppd.
1453 These signals cause pppd to terminate the link (by closing LCP),
1454 restore the serial device settings, and exit.
1457 This signal causes pppd to terminate the link, restore the serial
1458 device settings, and close the serial device. If the \fIpersist\fR or
1459 \fIdemand\fR option has been specified, pppd will try to reopen the
1460 serial device and start another connection (after the holdoff period).
1461 Otherwise pppd will exit. If this signal is received during the
1462 holdoff period, it causes pppd to end the holdoff period immediately.
1465 This signal toggles the state of the \fIdebug\fR option.
1468 This signal causes pppd to renegotiate compression. This can be
1469 useful to re-enable compression after it has been disabled as a result
1470 of a fatal decompression error. (Fatal decompression errors generally
1471 indicate a bug in one or other implementation.)
1474 Paul Mackerras (Paul.Mackerras@cs.anu.edu.au), based on earlier work by
projects / ppp.git / blob