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diff --git a/docs/system/net.texi b/docs/system/net.texi deleted file mode 100644 index 4a6fb2e6a8..0000000000 --- a/docs/system/net.texi +++ /dev/null @@ -1,96 +0,0 @@ -@node pcsys_network -@section Network emulation - -QEMU can simulate several network cards (e.g. PCI or ISA cards on the PC -target) and can connect them to a network backend on the host or an emulated -hub. The various host network backends can either be used to connect the NIC of -the guest to a real network (e.g. by using a TAP devices or the non-privileged -user mode network stack), or to other guest instances running in another QEMU -process (e.g. by using the socket host network backend). - -@subsection Using TAP network interfaces - -This is the standard way to connect QEMU to a real network. QEMU adds -a virtual network device on your host (called @code{tapN}), and you -can then configure it as if it was a real ethernet card. - -@subsubsection Linux host - -As an example, you can download the @file{linux-test-xxx.tar.gz} -archive and copy the script @file{qemu-ifup} in @file{/etc} and -configure properly @code{sudo} so that the command @code{ifconfig} -contained in @file{qemu-ifup} can be executed as root. You must verify -that your host kernel supports the TAP network interfaces: the -device @file{/dev/net/tun} must be present. - -See @ref{sec_invocation} to have examples of command lines using the -TAP network interfaces. - -@subsubsection Windows host - -There is a virtual ethernet driver for Windows 2000/XP systems, called -TAP-Win32. But it is not included in standard QEMU for Windows, -so you will need to get it separately. It is part of OpenVPN package, -so download OpenVPN from : @url{https://openvpn.net/}. - -@subsection Using the user mode network stack - -By using the option @option{-net user} (default configuration if no -@option{-net} option is specified), QEMU uses a completely user mode -network stack (you don't need root privilege to use the virtual -network). The virtual network configuration is the following: - -@example - - guest (10.0.2.15) <------> Firewall/DHCP server <-----> Internet - | (10.0.2.2) - | - ----> DNS server (10.0.2.3) - | - ----> SMB server (10.0.2.4) -@end example - -The QEMU VM behaves as if it was behind a firewall which blocks all -incoming connections. You can use a DHCP client to automatically -configure the network in the QEMU VM. The DHCP server assign addresses -to the hosts starting from 10.0.2.15. - -In order to check that the user mode network is working, you can ping -the address 10.0.2.2 and verify that you got an address in the range -10.0.2.x from the QEMU virtual DHCP server. - -Note that ICMP traffic in general does not work with user mode networking. -@code{ping}, aka. ICMP echo, to the local router (10.0.2.2) shall work, -however. If you're using QEMU on Linux >= 3.0, it can use unprivileged ICMP -ping sockets to allow @code{ping} to the Internet. The host admin has to set -the ping_group_range in order to grant access to those sockets. To allow ping -for GID 100 (usually users group): - -@example -echo 100 100 > /proc/sys/net/ipv4/ping_group_range -@end example - -When using the built-in TFTP server, the router is also the TFTP -server. - -When using the @option{'-netdev user,hostfwd=...'} option, TCP or UDP -connections can be redirected from the host to the guest. It allows for -example to redirect X11, telnet or SSH connections. - -@subsection Hubs - -QEMU can simulate several hubs. A hub can be thought of as a virtual connection -between several network devices. These devices can be for example QEMU virtual -ethernet cards or virtual Host ethernet devices (TAP devices). You can connect -guest NICs or host network backends to such a hub using the @option{-netdev -hubport} or @option{-nic hubport} options. The legacy @option{-net} option -also connects the given device to the emulated hub with ID 0 (i.e. the default -hub) unless you specify a netdev with @option{-net nic,netdev=xxx} here. - -@subsection Connecting emulated networks between QEMU instances - -Using the @option{-netdev socket} (or @option{-nic socket} or -@option{-net socket}) option, it is possible to create emulated -networks that span several QEMU instances. -See the description of the @option{-netdev socket} option in the -@ref{sec_invocation,,Invocation chapter} to have a basic example. |