Virtual network device (<code>venet</code>) is the default network device for a [[container]]. This Due to [[w:Network_Layer|Layer 3]] employed by OpenVZ's venet, 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).

vzctl set 101 --ipadd 10.0.0.1 --savevzctl set 101 --ipadd fd00::101 --save

== Sysctl == You will need to configure some sysctl parameters to get your Specific aspects of venet devices working.Please have a look at the [[Installation_on_Debian#sysctl]] section. == IPv6 == To setup IPv6 networking with venet you'll need to enable the following in your sysctl.conf: <code> # IPv6 Packet Forwarding and Proxy NDP net.ipv6.conf.default.forwarding = 1 net.ipv6.conf.all.forwarding = 1 net.ipv6.conf.default.proxy_ndp network device = 1 net.ipv6.conf.all.proxy_ndp = 1</code>

In IPv6 you can't control forwarding per === No [[w:Network_bridge|bridge]] support ===Venet network device, forwarding control has to take place in ip6tables, so all interfaces will forward IPv6 trafficcannot be bridged together and/or with other devices.

If you enable IPv6 forwarding for your interfaces=== No possiblity to assign an IP from the CT ===With venet device, Linux assumes your host only OpenVZ [[hardware node]] administrator can assign an IP address to act like a router and will ignore 'Router Advertisments' (see [http://en.wikipedia.org/wiki/Neighbor_Discovery_Protocol Neighbor Discovery Protocol[container] or [http://mirrors.bieringer.de/Linux+IPv6-HOWTO/proc-sys-net-ipv6.html Linux IPv6 Howto]).

You === Limited packet sniffing support ===Some applications using libpcap and similar packages will as well need to configure a new v6 default gateway for your host:report an error.

<code>=== No full support of IPv6 stack === ip addr add 2620:0:2d0:1::193/64 dev eth0 route venet devices are not fully IPv6 compliant. They do not properly support MAC addresses and consequently link local addresses and can not play nice with neighbor discovery or router advertisements, router discovery, or auto-6 add default gw 2620:0:2d0:1::1conf. They also require additional modifications to the layer 3 forwarding behaviour of the host via sysctl, to get your venet devices working.</code>Please have a look at the [[Quick installation#sysctl]] section.

You can add these commands to your existing network configuration veth devices do require iptables and ip6tables exceptions on Debian/Linux:the host for each VE address.

<code> iface eth0 inet static address 64You'll need to use the veth bridging device if you want full IPv6 compliance.131 See the [[VEs and HNs in same subnets]] article for an example.90.7 netmask 255.255.255.240 network 64.131.90.0 broadcast 64.131.90.15 gateway 64.131.90.1 up ip addr add 2620:0:2d0:1::193/64 dev eth0 up route -6 add default gw 2620:0:2d0:1::1 down ip addr del 3620:0:2d0:1::193/64 dev eth0</code>