Editing Virtual network device

Virtual network device (<code>venet</code>) is the default network device for a [[container]]. This network device looks like a point-to-point connection between [[container]] and the [[CT0|host system]]. It does packet switching based on IP header. This is a default network device for container (an alternative is [[veth]] device).

Venet device is created automatically on [[container]] start. Vzctl scripts set up an appropriate IP address and other settings on venet inside a container.

==  Usage ==

== Kernel module ==
First of all, check that <code>vznetdev</code> module is loaded:
<pre>
# lsmod | grep vznetdev
</pre>

If it is not, load the module:
<pre>
# modprobe vznetdev
</pre>

You might want to check /etc/init.d/vz script to make sure the module gets loaded during startup.

=== Adding IP address to a container ===
<pre>
vzctl set <CTID> --ipadd <IP1>[,<IP2>,...] [--save]
</pre>

{{Note|This option is incremental, so IP addresses are added to already existing ones.}}

==== Example ====
<pre>
vzctl set 101 --ipadd 10.0.0.1 --save
</pre>
After executing this command IP address 10.0.0.1 will be added to container 101 and IP configuration will be saved to a container configuration file.

=== Removing IP address from a container ===
<pre>
vzctl set <CTID> --ipdel <IP1>[,<IP2>,...] [--save]
vzctl set <CTID> --ipdel all [--save]
</pre>

==== Example ====
<pre>
vzctl set 101 --ipdel 10.0.0.1
</pre>
After executing this command IP address 10.0.0.1 will be removed from container 101, but IP configuration will not be changed in container config file. And after container reboot IP address 10.0.0.1 will be assigned to this container again.

== See also ==
* [[Veth]]
* [[Differences between venet and veth]]

[[Category: Networking]]
[[Category: HOWTO]]