-nic?[tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn]

此選項(xiàng)是一次性配置板載（默認(rèn)）來(lái)賓 NIC 硬件和主機(jī)網(wǎng)絡(luò)后端的快捷方式。主機(jī)后端選項(xiàng)與下面的相應(yīng)選項(xiàng)相同?？蛻魴C(jī)網(wǎng)卡模型可以使用 設(shè)置。用于列出可用的設(shè)備類型。硬件 MAC 地址可以使用 設(shè)置。-netdevmodel=modelnamemodel=helpmac=macaddr

以下兩個(gè)示例執(zhí)行完全相同操作，以演示如何使用命令行長(zhǎng)度：-nic

-nic?none

指示不應(yīng)配置任何網(wǎng)絡(luò)設(shè)備。它用于覆蓋默認(rèn)配置（帶有“用戶”主機(jī)網(wǎng)絡(luò)后端的默認(rèn) NIC），如果未提供其他網(wǎng)絡(luò)選項(xiàng)，則會(huì)激活該配置。

-netdev?user,id=id[,option][,option][,...]

配置用戶模式主機(jī)網(wǎng)絡(luò)后端，無(wú)需管理員權(quán)限即可運(yùn)行。有效選項(xiàng)包括：

• id=id

• 指定在監(jiān)視命令中使用的符號(hào)名稱。

• ipv4=on|off?and?ipv6=on|off

• 指定必須啟用 IPv4 或 IPv6。如果未指定任何協(xié)議，則啟用兩個(gè)協(xié)議。

• net=addr[/mask]

• 設(shè)置來(lái)賓將看到的 IP 網(wǎng)絡(luò)地址。（可選）以 a.b.c.d 的形式指定網(wǎng)絡(luò)掩碼，或指定為最頂部的有效位數(shù)。默認(rèn)值為 10.0.2.0/24。

• host=addr

• 指定主機(jī)的來(lái)賓可見(jiàn)地址。默認(rèn)值為來(lái)賓網(wǎng)絡(luò)中的第 2 個(gè) IP，即 x.x.x.2。

• ipv6-net=addr[/int]

• 設(shè)置來(lái)賓將看到的 IPv6 網(wǎng)絡(luò)地址（默認(rèn)值為 fec0：：/64）。網(wǎng)絡(luò)前綴以通常的十六進(jìn)制 IPv6 地址表示法給出。前綴大小是可選的，并作為最上面的有效位數(shù)給出（默認(rèn)值為 64）。

• ipv6-host=addr

• 指定主機(jī)的客戶機(jī)可見(jiàn) IPv6 地址。默認(rèn)值為來(lái)賓網(wǎng)絡(luò)中的第 2 個(gè) IPv6，即 xxxx：：2。

• restrict=on|off

• 如果啟用此選項(xiàng)，則來(lái)賓將被隔離，即它將無(wú)法聯(lián)系主機(jī)，并且不會(huì)將任何來(lái)賓 IP 數(shù)據(jù)包通過(guò)主機(jī)路由到外部。此選項(xiàng)不會(huì)影響任何顯式設(shè)置的轉(zhuǎn)發(fā)規(guī)則。

• hostname=name

• 指定內(nèi)置 DHCP 服務(wù)器報(bào)告的客戶機(jī)主機(jī)名。

• dhcpstart=addr

• 指定內(nèi)置 DHCP 服務(wù)器可以分配的 16 個(gè) IP 中的第一個(gè)。默認(rèn)值為來(lái)賓網(wǎng)絡(luò)中的第 15 個(gè)到第 31 個(gè) IP，即 x.x.x.15 到 x.x.x.31。

• dns=addr

• Specify the guest-visible address of the virtual nameserver. The address must be different from the host address. Default is the 3rd IP in the guest network, i.e. x.x.x.3.

• ipv6-dns=addr

• Specify the guest-visible address of the IPv6 virtual nameserver. The address must be different from the host address. Default is the 3rd IP in the guest network, i.e. xxxx::3.

• dnssearch=domain

• Provides an entry for the domain-search list sent by the built-in DHCP server. More than one domain suffix can be transmitted by specifying this option multiple times. If supported, this will cause the guest to automatically try to append the given domain suffix(es) in case a domain name can not be resolved.

  例：

  qemu-system-x86_64 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org

• domainname=domain

• Specifies the client domain name reported by the built-in DHCP server.

• tftp=dir

• When using the user mode network stack, activate a built-in TFTP server. The files in dir will be exposed as the root of a TFTP server. The TFTP client on the guest must be configured in binary mode (use the command?of the Unix TFTP client).bin

• tftp-server-name=name

• In BOOTP reply, broadcast name as the “TFTP server name” (RFC2132 option 66). This can be used to advise the guest to load boot files or configurations from a different server than the host address.

• bootfile=file

• When using the user mode network stack, broadcast file as the BOOTP filename. In conjunction with?, this can be used to network boot a guest from a local directory.tftp

  Example (using pxelinux):

  qemu-system-x86_64 -hda linux.img -boot n -device e1000,netdev=n1 \ ? ?-netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0

• smb=dir[,smbserver=addr]

• When using the user mode network stack, activate a built-in SMB server so that Windows OSes can access to the host files in?transparently. The IP address of the SMB server can be set to addr. By default the 4th IP in the guest network is used, i.e. x.x.x.4.dir

  In the guest Windows OS, the line:

  10.0.2.4 smbserver

  must be added in the file?(for windows 9x/Me) or?(Windows NT/2000).C:\WINDOWS\LMHOSTSC:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS

  Then?can be accessed in?.dir\\smbserver\qemu

  Note that a SAMBA server must be installed on the host OS.

• hostfwd=[tcp|udp]:[hostaddr]:hostport-[guestaddr]:guestport

• Redirect incoming TCP or UDP connections to the host port hostport to the guest IP address guestaddr on guest port guestport. If guestaddr is not specified, its value is x.x.x.15 (default first address given by the built-in DHCP server). By specifying hostaddr, the rule can be bound to a specific host interface. If no connection type is set, TCP is used. This option can be given multiple times.

  For example, to redirect host X11 connection from screen 1 to guest screen 0, use the following:

  # on the host qemu-system-x86_64 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 # this host xterm should open in the guest X11 server xterm -display :1

  To redirect telnet connections from host port 5555 to telnet port on the guest, use the following:

  # on the host qemu-system-x86_64 -nic user,hostfwd=tcp::5555-:23 telnet localhost 5555

  Then when you use on the host?, you connect to the guest telnet server.telnet?localhost?5555

• guestfwd=[tcp]:server:port-dev;?guestfwd=[tcp]:server:port-cmd:command

• Forward guest TCP connections to the IP address server on port port to the character device dev or to a program executed by cmd:command which gets spawned for each connection. This option can be given multiple times.

  You can either use a chardev directly and have that one used throughout QEMU’s lifetime, like in the following example:

  # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever # the guest accesses it qemu-system-x86_64 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321

  Or you can execute a command on every TCP connection established by the guest, so that QEMU behaves similar to an inetd process for that virtual server:

  # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 # and connect the TCP stream to its stdin/stdout qemu-system-x86_64 -nic ?'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'

-netdev?tap,id=id[,fd=h][,ifname=name][,script=file][,downscript=dfile][,br=bridge][,helper=helper]

Configure a host TAP network backend with ID id.

Use the network script file to configure it and the network script dfile to deconfigure it. If name is not provided, the OS automatically provides one. The default network configure script is?and the default network deconfigure script is?. Use?or?to disable script execution./etc/qemu-ifup/etc/qemu-ifdownscript=nodownscript=no

If running QEMU as an unprivileged user, use the network helper to configure the TAP interface and attach it to the bridge. The default network helper executable is?and the default bridge device is?./path/to/qemu-bridge-helperbr0

fd=h can be used to specify the handle of an already opened host TAP interface.

Examples:

-netdev?bridge,id=id[,br=bridge][,helper=helper]

Connect a host TAP network interface to a host bridge device.

Use the network helper helper to configure the TAP interface and attach it to the bridge. The default network helper executable is?and the default bridge device is?./path/to/qemu-bridge-helperbr0

Examples:

-netdev?socket,id=id[,fd=h][,listen=[host]:port][,connect=host:port]

This host network backend can be used to connect the guest’s network to another QEMU virtual machine using a TCP socket connection. If?is specified, QEMU waits for incoming connections on port (host is optional).?is used to connect to another QEMU instance using the?option.?=h specifies an already opened TCP socket.listenconnectlistenfd

例：

-netdev?socket,id=id[,fd=h][,mcast=maddr:port[,localaddr=addr]]

Configure a socket host network backend to share the guest’s network traffic with another QEMU virtual machines using a UDP multicast socket, effectively making a bus for every QEMU with same multicast address maddr and port. NOTES:

1. Several QEMU can be running on different hosts and share same bus (assuming correct multicast setup for these hosts).

2. mcast support is compatible with User Mode Linux (argument?), see?http://user-mode-linux.sf.net.ethN=mcast

3. Use?to specify an already opened UDP multicast socket.fd=h

例：

Example (User Mode Linux compat.):

Example (send packets from host’s 1.2.3.4):

-netdev?l2tpv3,id=id,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport],txsession=txsession[,rxsession=rxsession][,ipv6=on|off][,udp=on|off][,cookie64][,counter][,pincounter][,txcookie=txcookie][,rxcookie=rxcookie][,offset=offset]

Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3931) is a popular protocol to transport Ethernet (and other Layer 2) data frames between two systems. It is present in routers, firewalls and the Linux kernel (from version 3.3 onwards).

This transport allows a VM to communicate to another VM, router or firewall directly.

• src=srcaddr

• source address (mandatory)

• dst=dstaddr

• destination address (mandatory)

• udp

• select udp encapsulation (default is ip).

• srcport=srcport

• source udp port.

• dstport=dstport

• destination udp port.

• ipv6

• force v6, otherwise defaults to v4.

• rxcookie=rxcookie;?txcookie=txcookie

• Cookies are a weak form of security in the l2tpv3 specification. Their function is mostly to prevent misconfiguration. By default they are 32 bit.

• cookie64

• Set cookie size to 64 bit instead of the default 32

• counter=off

• Force a ‘cut-down’ L2TPv3 with no counter as in draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00

• pincounter=on

• Work around broken counter handling in peer. This may also help on networks which have packet reorder.

• offset=offset

• Add an extra offset between header and data

For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan on the remote Linux host 1.2.3.4:

-netdev?vde,id=id[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]

Configure VDE backend to connect to PORT n of a vde switch running on host and listening for incoming connections on socketpath. Use GROUP groupname and MODE octalmode to change default ownership and permissions for communication port. This option is only available if QEMU has been compiled with vde support enabled.

Example:

-netdev?vhost-user,chardev=id[,vhostforce=on|off][,queues=n]

Establish a vhost-user netdev, backed by a chardev id. The chardev should be a unix domain socket backed one. The vhost-user uses a specifically defined protocol to pass vhost ioctl replacement messages to an application on the other end of the socket. On non-MSIX guests, the feature can be forced with vhostforce. Use ‘queues=n’ to specify the number of queues to be created for multiqueue vhost-user.

Example:

-netdev?vhost-vdpa,vhostdev=/path/to/dev

Establish a vhost-vdpa netdev.

vDPA device is a device that uses a datapath which complies with the virtio specifications with a vendor specific control path. vDPA devices can be both physically located on the hardware or emulated by software.

-netdev?hubport,id=id,hubid=hubid[,netdev=nd]

Create a hub port on the emulated hub with ID hubid.

The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a single netdev. Alternatively, you can also connect the hubport to another netdev with ID nd by using the?option.netdev=nd

-net?nic[,netdev=nd][,macaddr=mac][,model=type]?[,name=name][,addr=addr][,vectors=v]

Legacy option to configure or create an on-board (or machine default) Network Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. the default hub), or to the netdev nd. If model is omitted, then the default NIC model associated with the machine type is used. Note that the default NIC model may change in future QEMU releases, so it is highly recommended to always specify a model. Optionally, the MAC address can be changed to mac, the device address set to addr (PCI cards only), and a name can be assigned for use in monitor commands. Optionally, for PCI cards, you can specify the number v of MSI-X vectors that the card should have; this option currently only affects virtio cards; set v = 0 to disable MSI-X. If no?option is specified, a single NIC is created. QEMU can emulate several different models of network card. Use?for a list of available devices for your target.-net-net?nic,model=help

-net?user|tap|bridge|socket|l2tpv3|vde[,...][,name=name]

Configure a host network backend (with the options corresponding to the same?option) and connect it to the emulated hub 0 (the default hub). Use name to specify the name of the hub port.-netdev