---
name: "if_disc"
section: "4"
platform: "linux"
package: "freebsd-manpages"
version: "6.0-5"
release: "Debian 4.0 (Etch)"
platforms: ["linux", "freebsd"]
url: "https://new.carta.tech/if_disc"
---

# if\_disc(4)

software discard network interface

## NAME

**disc** – software discard network interface

## SYNOPSIS

**device disc**

## DESCRIPTION

The **disc** interface is a software discard mechanism which may be used for performance analysis and/or software testing. As with other network interfaces, the discard 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)](/ioctl/2.md).

Each **disc** interface is created at runtime using interface cloning. This is most easily done with the [ifconfig(8)](/ifconfig/8.md) **create** command or using the *cloned\_interfaces* variable in [rc.conf(5)](/rc.conf/5.md).

## SEE ALSO

[inet(4)](/inet/4.md), [intro(4)](/intro/4.md)

## HISTORY

The **disc** device appears to have been derived from the [lo(4)](/lo/4.md) device around the time of 4.4BSD. This manpage was adapted from [lo(4)](/lo/4.md) and first appeared in FreeBSD 5.0.