From patchwork Mon May 14 07:56:00 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 912734 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 40ktQS44vqz9s0q for ; Mon, 14 May 2018 17:59:44 +1000 (AEST) Received: from localhost ([::1]:48796 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fI8OU-0001fD-C6 for incoming@patchwork.ozlabs.org; Mon, 14 May 2018 03:59:42 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57916) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fI8LF-0007oy-0B for qemu-devel@nongnu.org; Mon, 14 May 2018 03:56:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fI8LD-0004Uz-Ok for qemu-devel@nongnu.org; Mon, 14 May 2018 03:56:21 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:59332 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 1fI8LD-0004UB-A8 for qemu-devel@nongnu.org; Mon, 14 May 2018 03:56:19 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CD462FB667; Mon, 14 May 2018 07:56:18 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-146.pek2.redhat.com [10.72.12.146]) by smtp.corp.redhat.com (Postfix) with ESMTP id A2E5DAB3F8; Mon, 14 May 2018 07:56:16 +0000 (UTC) From: Jason Wang To: qemu-devel@nongnu.org, peter.maydell@linaro.org Date: Mon, 14 May 2018 15:56:00 +0800 Message-Id: <1526284560-20266-5-git-send-email-jasowang@redhat.com> In-Reply-To: <1526284560-20266-1-git-send-email-jasowang@redhat.com> References: <1526284560-20266-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Mon, 14 May 2018 07:56:18 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Mon, 14 May 2018 07:56:18 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jasowang@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] [PULL 4/4] 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: Thomas Huth , Jason Wang Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Thomas Huth '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 Reviewed-by: Stefan Hajnoczi Signed-off-by: Thomas Huth Signed-off-by: Jason Wang --- qemu-doc.texi | 42 +++++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 19 deletions(-) diff --git a/qemu-doc.texi b/qemu-doc.texi index 9216848..e2acac8 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 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{-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