Virtual Network (1)-How to use it in a guest

This article will tell you a question: KVM guest uses libvirt XML to define how to use virtual network?

1) Nat, route, isolated type

Defining virtual network in host creates a dummy bridge, which is the equivalent of a switch. The guest only needs to be connected to this switch.

In the XML of the guest, add:

# Virsh Edit vm...<interface type= ' network '/><source network= ' Net1 '/> ====>net1 is a virtual network already defined </ Interface>, .....

This is the simplest XML, which will automatically add some necessary information such as MAC,PCI address, model type, and so on after saving. Of course, you can specify it manually.

2) User (userspace slirp stack), Vhost-user,multicast Tunnel, TCP tunnel,udp unicast tunnel type

Can only be referenced by interface in the guest. If user is a type that is available to a non-privileged user provided by QEMU, you can refer to this:

<interface type= ' user '/> (mac,pci address, model type if not specified, will be generated automatically)

3) Bridge (use of exsiting host Linux Bridge)

There is a Linux bridge on its own, which can be defined as a network for guest (no more bridge creation) or directly to guest. The two approaches are essentially the same.

# Virsh Net-dumpxml birdge-net<network> <name>bridge-net</name> <forward mode= ' Birdge '/> < Bridge name= ' br0 '/> </network># virsh edit vm...<interface type= ' network ' > <source network= ' Bridge-net ' ></interface>

Direct to Guest by:

<interface type= ' bridge ' > <source bridge= ' br0 '/></interface>

4) Macvtap (including Bridge,vepa,private,passthrough four species), Hostdev

A network can be set as a interface pool, referenced in the form of a network, or can be referenced directly. The same 3), both ways are essentially the same.

Define Interface Pool

<network> <name>direct-macvtap</name> <forward mode= "Bridge" > <interface dev= "Eth20"/> <interface dev= "eth21"/> <interface dev= "eth22"/> <interface D ev= "eth23"/> <interface dev= "eth24"/> </forward> </network>

<network> <name>hostdev-net</name> <forward mode= ' hostdev ' managed= ' yes ' > <driver name= ' V Fio '/> <address type= ' pci ' domain= ' 0 ' bus= ' 4 ' slot= ' 0 ' function= ' 1 '/> <address type= ' pci ' domain= ' 0 ' bus = ' 4 ' slot= ' 0 ' function= ' 2 '/> <address type= ' pci ' domain= ' 0 ' bus= ' 4 ' slot= ' 0 ' function= ' 3 '/> </forward> </network>

Direct reference in Guest

# Virsh Edit vm...<interface type= ' direct ' > <source dev= ' enp0s25 ' mode= ' Vepa '/></interface>

# Virsh Edit vm ... <interface type= ' hostdev ' managed= ' yes ' > <source> <address type= ' PCI ' DOMA in= ' 0x0000 ' bus= ' 0x00 ' slot= ' 0x19 ' function= ' 0x0 '/> </source> </interface>

This article is from the "11517071" blog, please be sure to keep this source http://11527071.blog.51cto.com/11517071/1843234

Virtual Network (1)-How to use it in a guest