NAME¶
edsc
—
Ethernet discard network interface
SYNOPSIS¶
device edsc
DESCRIPTION¶
The
edsc
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
if_bridge(4) and
vlan(4).
As with other network interfaces, an
edsc
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
SIOCSIFADDR
ioctl(2) or
ifconfig(8) utility.
Each
edsc
interface is created at runtime
using interface cloning. This is most easily done with the
ifconfig(8)
create
command or using the
cloned_interfaces variable in
rc.conf(5).
SEE ALSO¶
ioctl(2),
arp(4),
if_bridge(4),
inet(4),
intro(4),
vlan(4),
rc.conf(5),
arp(8),
ifconfig(8)
HISTORY¶
The
edsc
device was derived from the
disc(4) device and first appeared in
FreeBSD 6.3. This manpage was adapted from
disc(4).
CAVEATS¶
Since outgoing packets are just discarded by
edsc
, ARP requests stay unreplied.
Consequently, an IP packet cannot be sent via
edsc
until a static
arp(4) entry is created for its next hop using
arp(8).
Initially an
edsc
interface has a zero link
level address. It can be changed with
ifconfig(8)
lladdr
if needed.