From patchwork Mon Apr 16 06:44:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 898484 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40Pf6K1Xyrz9s0b for ; Mon, 16 Apr 2018 16:46:00 +1000 (AEST) Received: from localhost ([::1]:49735 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f7xtm-0007LS-Mj for incoming@patchwork.ozlabs.org; Mon, 16 Apr 2018 02:45:58 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59765) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f7xsr-0007Hf-PA for qemu-devel@nongnu.org; Mon, 16 Apr 2018 02:45:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f7xsq-0007d5-JK for qemu-devel@nongnu.org; Mon, 16 Apr 2018 02:45:01 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:54552 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f7xsq-0007cl-DN for qemu-devel@nongnu.org; Mon, 16 Apr 2018 02:45:00 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F320C4072446; Mon, 16 Apr 2018 06:44:59 +0000 (UTC) Received: from thh440s.redhat.com (ovpn-116-76.ams2.redhat.com [10.36.116.76]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1F8E2111DCF6; Mon, 16 Apr 2018 06:44:57 +0000 (UTC) From: Thomas Huth To: qemu-devel@nongnu.org, Jason Wang Date: Mon, 16 Apr 2018 08:44:41 +0200 Message-Id: <1523861081-3600-4-git-send-email-thuth@redhat.com> In-Reply-To: <1523861081-3600-1-git-send-email-thuth@redhat.com> References: <1523861081-3600-1-git-send-email-thuth@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Mon, 16 Apr 2018 06:45:00 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Mon, 16 Apr 2018 06:45:00 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'thuth@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v3 for-2.13 3/3] net: Get rid of 'vlan' terminology and use 'hub' instead in the doc files X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Samuel Thibault , Stefan Hajnoczi , Paolo Bonzini Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 'vlan' is very confusing since it does not mean something like IEEE 802.1Q, but rather emulated hubs, so let's switch to that terminology instead. While we're at it, move the subsection about hub a little bit downward in the documentation (it's not as important anymore as it was before the invention of the -netdev parameter), and extend it a little bit. Buglink: https://bugs.launchpad.net/qemu/+bug/658904 Signed-off-by: Thomas Huth Reviewed-by: Stefan Hajnoczi --- qemu-doc.texi | 42 +++++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 19 deletions(-) diff --git a/qemu-doc.texi b/qemu-doc.texi index b901cc2..f058341 100644 --- a/qemu-doc.texi +++ b/qemu-doc.texi @@ -714,20 +714,12 @@ state is not saved or restored properly (in particular USB). @node pcsys_network @section Network emulation -QEMU can simulate several network cards (PCI or ISA cards on the PC -target) and can connect them to an arbitrary number of Virtual Local -Area Networks (VLANs). Host TAP devices can be connected to any QEMU -VLAN. VLAN can be connected between separate instances of QEMU to -simulate large networks. For simpler usage, a non privileged user mode -network stack can replace the TAP device to have a basic network -connection. - -@subsection VLANs - -QEMU simulates several VLANs. A VLAN can be symbolised 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). +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 @@ -763,7 +755,7 @@ network). The virtual network configuration is the following: @example - QEMU VLAN <------> Firewall/DHCP server <-----> Internet + guest (10.0.2.15) <------> Firewall/DHCP server <-----> Internet | (10.0.2.2) | ----> DNS server (10.0.2.3) @@ -798,11 +790,23 @@ 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 Connecting VLANs between QEMU instances +@subsection Hubs + +QEMU can simulate several hubs. A hub can be symbolised 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{-net socket} option, it is possible to make VLANs -that span several QEMU instances. See @ref{sec_invocation} to have a -basic example. +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. @node pcsys_other_devs @section Other Devices