.\"
.\" Written by Archie Cobbs <archie@freebsd.org>
.\" Copyright (c) 1995-1999 Whistle Communications, Inc. All rights reserved.
.\" See ``COPYRIGHT.whistle''
.\"
.Dd 2013-06-11
.Dt MPD5 8
.Os
.Sh NAME
.Nm mpd5
.Nd netgraph multi-link PPP daemon
.Sh SYNOPSIS
.Nm
.Op Fl bkov
.Op Fl d Ar directory
.Op Fl f Ar file
.Op Fl p Ar pid-file
.Op Fl s Ar ident
.Op Fl m Ar service
.Op Ar configuration
.Sh DESCRIPTION
.Nm
is a user mode PPP daemon using the
.Xr netgraph 4
networking system.
By using Netgraph,
.Nm
combines the robustness and flexibility of a user-mode PPP implementation
with the speed and reliability of kernel-mode packet forwarding.
All PPP negotiation is handled in user level code, while all data
intensive operations such as encryption, compression, and multi-link
framing are handled strictly in the kernel.
Mpd supports several link layer types, a fully event-driven modem chat
scripting language, and other features.
.Pp
.Nm
creates a
.Xr ng_ppp 4
netgraph node that is placed between a
.Xr ng_iface 4
netgraph interface one or more link layer devices,
performing multi-link PPP negotiation and encapsulation. In multi-link PPP a
.Ar bundle
is a collection of one or more
.Ar links 
between two peers. Each link corresponds to some device (e.g.,
a modem), and each bundle corresponds to one netgraph interface.
The idea is to use all of the links, together connected to a remote
peer also performing multi-link PPP, to utilize their combined
bandwidth.  Packets routed through the netgraph interface travel in
multi-link fragments over all of the links.
Each link is a normal PPP link and can deliver complete packets
as well, so redundancy is another benefit.
Attempts to connect two links in the same bundle to different peers,
or to a peer that is not configured for multi-link PPP, will fail.
.Pp
In general, everything is controlled by executing commands which are either
entered via the console command line or read from a configuration file. If
.Nm
is running as a background daemon, the console can be made accessible via
.Xr telnet 1
Since commands may apply to a single link, the console prompt always shows the
.Ar current bundle
or the
.Ar current link
in that bundle. 
.Sh ON-LINE MANUAL
Mpd is fully documented in the mpd manual, which is available in HTML.
The manual can be found in the directory
.Pa /usr/local/share/doc/mpd5 .
.Sh OPTIONS
Mpd supports the following command options:
.Pp
.Bl -tag -width Ds -compact
.Pp
.It Fl b
.It Fl -background
.Pp
Detach from the terminal and run as a background deamon.
.Pp
.It Fl d Ar dirname
.It Fl -directory Ar dirname
.Pp
Specify a configuration directory other than the default,
.Pa /usr/local/etc/mpd5 .
.Pp
.It Fl f Ar file
.It Fl -file Ar file
.Pp
Specify an initial configuration file other than the default,
.Pa mpd.conf .
.Pp
.It Fl o
.It Fl -one-shot
.Pp
Terminate daemon after the last link shutdown.
.Pp
.It Fl p Ar file
.It Fl -pidfile Ar file
.Pp
Specify an lock/process ID storage file other than the default
.Pa /var/run/mpd.pid .
.Pp
.It Fl k
.It Fl -kill
.Pp
Kill any existing
.Nm
daemon currently running. The same pidfile must be used.
.Pp
.It Fl s Ar ident
.It Fl -syslog-ident Ar ident
.Pp
Identifier to use for
.Xr syslog 3 .
The default -
.Pa mpd
.Pp
.It Fl m Ar service
.It Fl -pam-service Ar service
.Pp
Service name to use for
.Xr pam 3 .
The default -
.Pa mpd
.Pp
.It Fl v
.It Fl -version
.Pp
Display the program version and exit.
.Pp
.It Fl h
.It Fl -help
.Pp
Display invocation usage and exit.
.El
.Sh FILES
.Bl -tag -width /usr/local/share/doc/mpdXX -compact
.It Pa /usr/local/share/doc/mpd5
Directory containing the mpd manual
.It Pa /usr/local/etc/mpd5
Default configuration file directory
.It Pa mpd.conf
Configuration file
.It Pa mpd.script
Modem chat scripts
.It Pa mpd.secret
Account name, password pairs
.It Pa /var/run/mpd.pid
Stored process ID and lock file
.El
.Sh SEE ALSO
.Xr netgraph 4 ,
.Xr ngctl 8 ,
.Xr ng_ppp 4 ,
.Xr ng_iface 4 ,
.Xr ppp 8 .
.Sh AUTHORS
.An Archie Cobbs Aq archie@FreeBSD.org
.An Alexander Motin Aq mav@FreeBSD.org
.An based on ppp daemon written by Toshiharu OHNO Aq tony-o@iij.ad.jp