veth(4) — Linux manual page


VETH(4)                   Linux Programmer's Manual                  VETH(4)

NAME         top

       veth - Virtual Ethernet Device

DESCRIPTION         top

       The veth devices are virtual Ethernet devices.  They can act as
       tunnels between network namespaces to create a bridge to a physical
       network device in another namespace, but can also be used as
       standalone network devices.

       veth devices are always created in interconnected pairs.  A pair can
       be created using the command:

           # ip link add <p1-name> type veth peer name <p2-name>

       In the above, p1-name and p2-name are the names assigned to the two
       connected end points.

       Packets transmitted on one device in the pair are immediately
       received on the other device.  When either devices is down the link
       state of the pair is down.

       veth device pairs are useful for combining the network facilities of
       the kernel together in interesting ways.  A particularly interesting
       use case is to place one end of a veth pair in one network namespace
       and the other end in another network namespace, thus allowing commu‐
       nication between network namespaces.  To do this, one can provide the
       netns parameter when creating the interfaces:

           # ip link add <p1-name> netns <p1-ns> type veth peer <p2-name> netns <p2-ns>

       or, for an existing veth pair, move one side to the other namespace:

           # ip link set <p2-name> netns <p2-ns>

       ethtool(8) can be used to find the peer of a veth network interface,
       using commands something like:

           # ip link add ve_A type veth peer name ve_B   # Create veth pair
           # ethtool -S ve_A         # Discover interface index of peer
           NIC statistics:
                peer_ifindex: 16
           # ip link | grep '^16:'   # Look up interface
           16: ve_B@ve_A: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc ...

SEE ALSO         top

       clone(2), network_namespaces(7), ip(8), ip-link(8), ip-netns(8)

COLOPHON         top

       This page is part of release 5.08 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at

Linux                            2020-06-09                          VETH(4)

Pages that refer to this page: network_namespaces(7)