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From: @(#)lo.4 8.1 (Berkeley) 6/5/93
$FreeBSD$
.Dd March 25, 2007 .Dt EDSC 4 .Os .Sh NAME .Nm edsc .Nd Ethernet discard network interface .Sh SYNOPSIS .Cd "device edsc" .Sh DESCRIPTION The .Nm interface is a software discard mechanism which may be used for performance analysis and software testing. It imitates an Ethernet device, which allows for its use in conjunction with such drivers as .Xr if_bridge 4 and .Xr vlan 4 .
p As with other network interfaces, an .Nm interface must have network addresses assigned for each address family with which it is to be used. These addresses may be set or changed with the .Dv SIOCSIFADDR .Xr ioctl 2 or .Xr ifconfig 8 utility.
p Each .Nm interface is created at runtime using interface cloning. This is most easily done with the .Xr ifconfig 8 .Cm create command or using the .Va cloned_interfaces variable in .Xr rc.conf 5 . .Sh SEE ALSO .Xr ioctl 2 , .Xr arp 4 , .Xr if_bridge 4 , .Xr inet 4 , .Xr intro 4 , .Xr vlan 4 , .Xr rc.conf 5 , .Xr arp 8 , .Xr ifconfig 8 .Sh HISTORY The .Nm device was derived from the .Xr disc 4 device and first appeared in .Fx 6.3 . This manpage was adapted from .Xr disc 4 . .Sh CAVEATS Since outgoing packets are just discarded by .Nm , ARP requests stay unreplied. Consequently, an IP packet cannot be sent via .Nm until a static .Xr arp 4 entry is created for its next hop using .Xr arp 8 .
p Initially an .Nm interface has a zero link level address. It can be changed with .Xr ifconfig 8 .Cm lladdr if needed.