112 lines
3.3 KiB
Groff
112 lines
3.3 KiB
Groff
.\" Copyright (c) 1983, 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" From: @(#)lo.4 8.1 (Berkeley) 6/5/93
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.\" $FreeBSD$
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.\"
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.Dd March 25, 2007
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.Dt EDSC 4
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.Os
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.Sh NAME
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.Nm edsc
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.Nd Ethernet discard network interface
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.Sh SYNOPSIS
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.Cd "device edsc"
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.Sh DESCRIPTION
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The
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.Nm
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interface is a software discard mechanism which may be
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used for performance analysis and software testing.
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It imitates an Ethernet device, which
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allows for its use in conjunction with such drivers as
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.Xr if_bridge 4
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and
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.Xr vlan 4 .
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.Pp
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As with other network interfaces, an
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.Nm
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interface must have network addresses assigned for each address family
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with which it is to be used.
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These addresses may be set or changed with the
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.Dv SIOCSIFADDR
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.Xr ioctl 2
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or
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.Xr ifconfig 8
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utility.
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.Pp
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Each
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.Nm
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interface is created at runtime using interface cloning.
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This is most easily done with the
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.Xr ifconfig 8
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.Cm create
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command or using the
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.Va cloned_interfaces
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variable in
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.Xr rc.conf 5 .
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.Sh SEE ALSO
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.Xr ioctl 2 ,
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.Xr arp 4 ,
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.Xr if_bridge 4 ,
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.Xr inet 4 ,
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.Xr intro 4 ,
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.Xr vlan 4 ,
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.Xr rc.conf 5 ,
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.Xr arp 8 ,
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.Xr ifconfig 8
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.Sh HISTORY
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The
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.Nm
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device was derived from the
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.Xr disc 4
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device and first appeared in
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.Fx 6.3 .
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This manpage was adapted from
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.Xr disc 4 .
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.Sh CAVEATS
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Since outgoing packets are just discarded by
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.Nm ,
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ARP requests stay unreplied.
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Consequently, an IP packet cannot be sent via
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.Nm
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until a static
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.Xr arp 4
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entry is created for its next hop using
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.Xr arp 8 .
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.Pp
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Initially an
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.Nm
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interface has a zero link level address.
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It can be changed with
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.Xr ifconfig 8
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.Cm lladdr
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if needed.
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