Путеводитель по Руководству Linux
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   pppd    ( 8 )

демон протокола точка-точка (Point-to-Point Protocol Daemon)
  Name  |  Synopsis  |  Description  |    Frequently used options    |  Options  |  Pppoe options  |  Options files  |  Security  |  Authentication  |  Routing  |  Multilink  |  Examples  |  Diagnostic  |  Exit  |  Scripts  |  Files  |  See also  |  Note  |

FREQUENTLY USED OPTIONS

ttyname Use the serial port called ttyname to communicate with the peer. If ttyname does not begin with a slash (/), the string "/dev/" is prepended to ttyname to form the name of the device to open. If no device name is given, or if the name of the terminal connected to the standard input is given, pppd will use that terminal, and will not fork to put itself in the background. A value for this option from a privileged source cannot be overridden by a non- privileged user.

speed An option that is a decimal number is taken as the desired baud rate for the serial device. On systems such as Linux, 4.4BSD and NetBSD, any speed can be specified. Other systems (e.g. SunOS) only support the commonly-used baud rates.

asyncmap map This option sets the Async-Control-Character-Map (ACCM) for this end of the link. The ACCM is a set of 32 bits, one for each of the ASCII control characters with values from 0 to 31, where a 1 bit indicates that the corresponding control character should not be used in PPP packets sent to this system. The map is encoded as a hexadecimal number (without a leading 0x) where the least significant bit (00000001) represents character 0 and the most significant bit (80000000) represents character 31. Pppd will ask the peer to send these characters as a 2-byte escape sequence. If multiple asyncmap options are given, the values are ORed together. If no asyncmap option is given, the default is zero, so pppd will ask the peer not to escape any control characters. To escape transmitted characters, use the escape option.

auth Require the peer to authenticate itself before allowing network packets to be sent or received. This option is the default if the system has a default route. If neither this option nor the noauth option is specified, pppd will only allow the peer to use IP addresses to which the system does not already have a route.

call name Read additional options from the file /etc/ppp/peers/name. This file may contain privileged options, such as noauth, even if pppd is not being run by root. The name string may not begin with / or include .. as a pathname component. The format of the options file is described below.

connect script Usually there is something which needs to be done to prepare the link before the PPP protocol can be started; for instance, with a dial-up modem, commands need to be sent to the modem to dial the appropriate phone number. This option specifies an command for pppd to execute (by passing it to a shell) before attempting to start PPP negotiation. The chat (8) program is often useful here, as it provides a way to send arbitrary strings to a modem and respond to received characters. A value for this option from a privileged source cannot be overridden by a non-privileged user.

crtscts Specifies that pppd should set the serial port to use hardware flow control using the RTS and CTS signals in the RS-232 interface. If neither the crtscts, the nocrtscts, the cdtrcts nor the nocdtrcts option is given, the hardware flow control setting for the serial port is left unchanged. Some serial ports (such as Macintosh serial ports) lack a true RTS output. Such serial ports use this mode to implement unidirectional flow control. The serial port will suspend transmission when requested by the modem (via CTS) but will be unable to request the modem to stop sending to the computer. This mode retains the ability to use DTR as a modem control line.

defaultroute Add a default route to the system routing tables, using the peer as the gateway, when IPCP negotiation is successfully completed. This entry is removed when the PPP connection is broken. This option is privileged if the nodefaultroute option has been specified.

defaultroute-metric Define the metric of the defaultroute and only add it if there is no other default route with the same metric. With the default value of -1, the route is only added if there is no default route at all.

replacedefaultroute This option is a flag to the defaultroute option. If defaultroute is set and this flag is also set, pppd replaces an existing default route with the new default route. This option is privileged.

disconnect script Execute the command specified by script, by passing it to a shell, after pppd has terminated the link. This command could, for example, issue commands to the modem to cause it to hang up if hardware modem control signals were not available. The disconnect script is not run if the modem has already hung up. A value for this option from a privileged source cannot be overridden by a non-privileged user.

escape xx,yy,... Specifies that certain characters should be escaped on transmission (regardless of whether the peer requests them to be escaped with its async control character map). The characters to be escaped are specified as a list of hex numbers separated by commas. Note that almost any character can be specified for the escape option, unlike the asyncmap option which only allows control characters to be specified. The characters which may not be escaped are those with hex values 0x20 - 0x3f or 0x5e.

file name Read options from file name (the format is described below). The file must be readable by the user who has invoked pppd.

init script Execute the command specified by script, by passing it to a shell, to initialize the serial line. This script would typically use the chat(8) program to configure the modem to enable auto answer. A value for this option from a privileged source cannot be overridden by a non-privileged user.

lock Specifies that pppd should create a UUCP-style lock file for the serial device to ensure exclusive access to the device. By default, pppd will not create a lock file.

mru n Set the MRU [Maximum Receive Unit] value to n. Pppd will ask the peer to send packets of no more than n bytes. The value of n must be between 128 and 16384; the default is 1500. A value of 296 works well on very slow links (40 bytes for TCP/IP header + 256 bytes of data). Note that for the IPv6 protocol, the MRU must be at least 1280.

mtu n Set the MTU [Maximum Transmit Unit] value to n. Unless the peer requests a smaller value via MRU negotiation, pppd will request that the kernel networking code send data packets of no more than n bytes through the PPP network interface. Note that for the IPv6 protocol, the MTU must be at least 1280.

passive Enables the "passive" option in the LCP. With this option, pppd will attempt to initiate a connection; if no reply is received from the peer, pppd will then just wait passively for a valid LCP packet from the peer, instead of exiting, as it would without this option.