Copyright (c) 2001 Martin Husemann. All rights reserved.
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.Dd December 10, 2001 .Dt PPPOE 4 .Os .Sh NAME .Nm pppoe .Nd PPP over ethernet protocol network interface .Sh SYNOPSIS .Nm pseudo-device pppoe .Sh DESCRIPTION The .Nm interface encapsulatates .Em Point-to-Point Protocol (PPP) packets inside ehternet frames as defined by .Li RFC2516 .
p This is often used to connect a router via a DSL modem to an access concentrator. The .Nm interface does not by itself transmit or receive frames, but needs an ethernet interface to do so. This ethernet interface is connected to the .Nm interface via .Xr pppoectl 8 . The ethernet interface needs to be marked UP, but does not need to have an IP address.
p There are two basic modes of operation, controlled via the .Em link1 switch. The default mode, .Em link1 not being set, tries to keep the configured session open all the time. If the session is disconnected, a new connection attempt is started imediately. The .Dq dial on demand mode, selected by setting .Em link1 , only establishes a connection when data is being sent to the interface.
p Before a .Nm interface is useable, it needs to be configured. The following steps are necessary: l -bullet t create the interface t connect an ethernet interface This interface is used for the physical communication. As noted above it must be marked UP, but need not have an IP address. t configure authentication The PPP session needs to identify the client to the peer. For more details on the available options see .Xr pppoectl 8 . .El This all is typically done in an /etc/ifconfig.pppoe0 file. .Sh EXAMPLES A typical /etc/ifconfig.pppoe0 file looks like this: d -literal create ! /sbin/ifconfig ne0 up ! /sbin/pppoectl -e ne0 $int ! /sbin/pppoectl $int myauthproto=pap myauthname=testcaller myauthsecret=donttell inet 0.0.0.0 0.0.0.1 #! /sbin/route add default -iface 0.0.0.1 up .Ed The commented out call to .Xr route 8 may be ommited and the route added in the ip-up script called by .Xr ifwatchd 8 , when the real IP address is known. This is easy in the .Dq connect always mode (link1 not set), but hard to acomplish in the .Dq dial on demand mode (link1 set). In the latter case adding an iface route is an easy workaround.
p The .Nm interfaces operate completely inside the kernel, without any userland support. Because of this, a special deamon is used to fire ip-up or down scripts to execute arbitrary code when the PPP session is established and addresses of the interface become available. To enable the useage of /etc/ppp/ip-up and /etc/ppp/ip-down for this purpose, simply add d -literal ifwatchd=YES .Ed to /etc/rc.conf. See .Xr ifwatchd 8 for details and parameters passed to this scripts.
p Since this is a PPP interface, the addresses assigned to the interface may change during PPP negotiation. There is no fine grained control available, which addresses are acceptable and which are not. For the local side and the remote address there is exactly one choice: hard code address or wildcard. If a real address is assigned to one side of the connection, PPP negotiation will only aggree to exactly this address. If one side is wildcarded, every address suggested by the peer will be accepted.
p To wildcard the local address set it to 0.0.0.0, to wildcard the remote address set it to 0.0.0.1. Wildcarding is not available (nor necessary) for IPv6 operation. .Sh BUGS This implementation is client side only. .Sh SEE ALSO .Xr pppoectl 8 , .Xr ifwatchd 8 .Rs .%R RFC .%N 2516 .%D February 1999 .%T "A Method for Transmitting PPP Over Ethernet (PPPoE)" .Re .Sh HISTORY The .Nm device appeared in .Nx 1.6 .
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