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ETHERIP(4) NetBSD Kernel Interfaces Manual ETHERIP(4)
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etherip -- EtherIP tunneling device
The etherip interface is a tunneling pseudo device for Ethernet frames.
It can tunnel Ethernet traffic over IPv4 and IPv6 using the EtherIP pro-
tocol specified in RFC 3378.
The only difference between an etherip interface and a real Ethernet
interface is that there is an IP tunnel instead of a wire. Therefore, to
use etherip the administrator must first create the interface and then
configure protocol and addresses used for the outer header. This can be
done by using ifconfig(8) create and tunnel subcommands, or SIOCIFCREATE
and SIOCSLIFPHYADDR ioctls.
Ethernet frames are prepended with a EtherIP header as described by RFC
3378. The resulting EtherIP packets will be encapsulated in an outer
packet, which may be either an IPv4 or IPv6 packet, with IP protocol num-
When a etherip device is created, it is assigned an Ethernet address of
the form f2:0b:a5:xx:xx:xx. This address can later be changed through a
The sysctl node is net.link.etherip.<iface>. Any string of six colon-
separated hexadecimal numbers will be accepted. Reading that node will
provide a string representation of the current Ethernet address.
The EtherIP header of incoming packets is not checked for validity. This
is because there seems to be some confusion about how such a header has
to look like. For outgoing packets, the header is set up the same way as
done in OpenBSD, FreeBSD, and Linux to be compatible with those systems.
Converting from previous implementation
A tunnel configured for the previous (undocumented) implementation will
work with just renaming the device from gif to etherip.
bridge(4), gif(4), inet(4), inet6(4), tap(4), ifconfig(8)
The etherip device first appeared in NetBSD 4.0, it is based on tap(4),
gif(4), and the former gif-based EtherIP implementation ported from
Probably many. There is lots of code duplication between etherip,
tap(4), gif(4), and probably other tunnelling drivers which should be
NetBSD 5.0 November 23, 2006 NetBSD 5.0