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.