Date: Sun, 21 Dec 2008 17:51:21 +0100 (CET) From: Juergen Lock <nox@jelal.kn-bremen.de> To: loader@FreeBSD.org Cc: freebsd-doc@FreeBSD.org, murray@FreeBSD.org Subject: Re: docs/127923: Please mention qemu in the FreeBSD Handbook Message-ID: <200812211651.mBLGpLd5005216@saturn.kn-bremen.de> In-Reply-To: <200812171626.mBHGQL0K035212@freefall.freebsd.org> References: <200812150128.mBF1Sehd094548@freefall.freebsd.org> <20081215130236.B5E051D703EF@mail.freebsdmall.com>
next in thread | previous in thread | raw e-mail | index | archive | help
In article <200812171626.mBHGQL0K035212@freefall.freebsd.org> you write: >loader <loader@freebsdmall.com> wrote: > >>> http://www.freebsd.org/cgi/query-pr.cgi?pr=127923 > >And I reworded some parts of Juergen's patch >with the help of murray@. > A few minor nits: >Index: chapter.sgml >=================================================================== >RCS file: /home/ncvs/doc/en_US.ISO8859-1/books/handbook/virtualization/chapter.sgml,v >retrieving revision 1.17 >diff -u -r1.17 chapter.sgml >--- chapter.sgml 28 Jul 2008 14:33:51 -0000 1.17 >+++ chapter.sgml 17 Dec 2008 16:13:40 -0000 >@@ -54,6 +54,11 @@ > virtualization.</para> > </listitem> > >+ <listitem> >+ <para>How to run FreeBSD as guest in <application>qemu</application> >+ and as a qemu host.</para> >+ </listitem> >+ > </itemizedlist> > > <para>Before reading this chapter, you should:</para> >@@ -969,6 +974,327 @@ > Work is also ongoing in getting <application>&xen;</application> to > work as a host environment on FreeBSD.</para> > >+ <sect2 id="virtualization-host-qemu"> >+ <sect2info> >+ <authorgroup> >+ <author> >+ <firstname>Juergen</firstname> >+ <surname>Lock</surname> >+ <contrib>Contributed by </contrib> >+ </author> >+ </authorgroup> >+ </sect2info> >+ <title><application>QEMU</application> on &os; as Host</title> >+ >+ <para><ulink url="http://bellard.org/qemu/">QEMU</ulink>; >+ is a generic processor emulator using dynamic binary translation >+ to achieve a reasonable emulation speed.</para> >+ >+ <sect3 id="virtualization-host-qemu-installation"> >+ <title>Installation</title> >+ >+ <para>There are two <application>QEMU</application> ports in the &os; >+ Ports tree at the moment: >+ <filename role="package">emulators/qemu</filename> >+ is usually the latest release, and >+ <filename role="package">emulators/qemu-devel</filename>. >+ is an svn snapshot. For best results try the latest version >+ available as a &os; package, or alternatively try the >+ <filename role="package">emulators/qemu-devel</filename>.</para> >+ >+ <para>Install <filename role="package">emulators/qemu-devel</filename> >+ with the following commands:</para> >+ >+ <screen>&prompt.root; <userinput>cd /usr/ports/emulators/qemu-devel</userinput> >+&prompt.root; <userinput>make install clean</userinput></screen> >+ >+ <para>If the <application>QEMU</application> port is built with the >+ kqemu knob enabled, load the kqemu kernel module:</para> >+ >+ <screen>&prompt.root; <userinput>kldload kqemu</userinput></screen> >+ >+ <para>And kqemu can be loaded automatically at boot by adding >+ the following line to <filename>/etc/rc.conf</filename>:</para> >+ >+ <programlisting>kqemu_enable="YES"</programlisting> >+ >+ <para>Please make sure the <filename>kqemu.ko</filename> is always in sync >+ with the kernel like with any kld installed outside of the base. Rebuild >+ the port <filename role="package">emulators/kqemu-kmod</filename> or >+ <filename role="package">emulators/kqemu-kmod-devel</filename> >+ whenever you update the kernel.</para> >+ >+ <para><application>QEMU</application> now uses &man.aio.4; at least >+ for IDE DMA, otherwise <application>QEMU</application> crashes >+ with <quote>Invalid system call</quote>:</para> >+ >+ <screen>&prompt.root; <userinput>kldload aio</userinput></screen> >+ >+ <note> >+ <para>If you want to run <application>QEMU</application> with >+ <option>-m</option> 512 or larger on &os; 6.3 i386 hosts, This most likely also applies to 6.4. >+ <varname>kern.maxdsiz</varname> needs to be increased in >+ <filename>/boot/loader.conf</filename> since the default >+ value is 512 MB, and <application>QEMU</application> needs >+ memory for itself also. &os; 7.0 and up use jemalloc which uses >+ &man.mmap.2; and isn't affected by >+ <varname>kern.maxdsiz</varname> anymore.</para> >+ </note> >+ </sect3> >+ >+ <sect3 id="virtualization-host-qemu-fbsdguest"> >+ <title>An example of installing &os; 7.0 as a >+ <application>QEMU</application> guest</title> >+ >+ <para>First, create an empty raw 5 GB image:</para> >+ >+ <screen>&prompt.user; <userinput>qemu-img create 7.0.img 5G</userinput></screen> >+ >+ <note> >+ <para>qcow2 is the <application>QEMU</application> image format, >+ use the <option>-f</option> qcow2 option to avoid sparse files >+ on the host. Some backup applications like &man.bsdtar.1; don't >+ support them properly, others like <application>gtar</application> >+ or <application>star</application> do if passed appropriate flags, >+ qcow2 format might be slower than raw format.</para> >+ </note> >+ >+ <para>Next, boot sysinstall with the image:</para> >+ >+ <screen>&prompt.user; <userinput>qemu -m 256 -cdrom 7.0-RELEASE-i386-disc1.iso -hda 7.0.img -boot d -monitor stdio</userinput></screen> >+ >+ <note> >+ <para>You need to run <command>qemu-system-x86_64</command> >+ if you want to emulate a amd64 guest.</para> ..an amd64 guest? >+ </note> >+ >+ <para>Now follow the instructions in <xref linkend="install"> like >+ as if you would install a real machine using CD media. >+ Click into the guest window to access the guest mouse pointer >+ and hit <keycombo action="simul"><keycap>Alt</keycap> >+ <keycap>Ctrl</keycap></keycombo> to leave the guest window >+ mouse grab. If you use the default usermode networking (aka slirp) >+ like in the above example the guest should have network if you >+ configure it to use DHCP, so if you want you could probably >+ also use a bootonly iso instead of disc1 and do a network install. >+ (&man.ping.8; doesn't work with slirp though.)</para> >+ >+ <para>When finished, select <quote>exit install</quote> in sysinstall to reboot, >+ and when the guest booting the ISO again, type >+ <command>q</command> in <application>QEMU</application>'s monitor or >+ <command>killall</command> qemu on another host shell if you are ... <command>killall qemu</command> ... ? >+ using <option>-curses</option>, like when you have no X11 on the >+ host.</para> >+ >+ <para>Now, boot the installed image:</para> >+ >+ <screen>&prompt.user; <userinput>qemu -m 256 -cdrom 7.0-RELEASE-i386-disc1.iso -hda 7.0.img -boot c -monitor stdio</userinput></screen> >+ >+ <para>Now you should see a normal boot like on a freshly installed >+ box, all the way up to your first login prompt. If you plan to >+ use this guest with <option>-nographic</option> later on, >+ now is the time to configure it for a serial console in the guest:</para> >+ >+ <screen>&prompt.root; <userinput>echo console=\"comconsole\" >>/boot/loader.conf</userinput> >+&prompt.root; <userinput>sed -i -e '/^ttyu0/s/off/on/' /etc/ttys</userinput></screen> >+ >+ <para>As always with virtualization, lowering <varname>kern.hz</varname> >+ helps performance also with <application>QEMU</application>:</para> >+ >+ <screen>&prompt.root; <userinput>echo kern.hz=100 >>/boot/loader.conf</userinput></screen> >+ >+ <para>When you are finished with the guest, shut it down, this should >+ make <application>QEMU</application> quit gracefully:</para> >+ >+ <screen>&prompt.root; <userinput>shutdown -p now</userinput></screen> >+ >+ <para>If the serial console is configured, now you can boot the >+ guest with <option>-nographic</option>:</para> >+ >+ <screen>&prompt.user; <userinput>qemu -m 256 -hda 7.0.img -boot c -nographic</userinput></screen> >+ >+ <para>With <option>-nographic</option>, the guest console and >+ <application>QEMU</application>'s monitor are multiplexed on >+ <application>QEMU</application>'s tty, hit >+ <keycombo action="simul"><keycap>Ctrl</keycap> >+ <keycap>a</keycap></keycombo> and then >+ <keycap>h</keycap> to show a small help.</para> >+ >+ <note> >+ <para>Qemu can emulate several different mode of network card, >+ try <option>pcnet</option>, <option>i82557b</option> >+ or <option>e1000</option>, they should be faster >+ and use less guest <acronym>CPU</acronym> than the >+ default <option>ne2kpci</option>.</para> >+ >+ <para>With the <option>-vnc</option> <replaceable>display</replaceable> >+ option, <application>QEMU</application> will listen on >+ <acronym>VNC</acronym> display <replaceable>display</replaceable> >+ and redirect the <acronym>VGA</acronym> display over the >+ <acronym>VNC</acronym> session. If the host or >+ <application>QEMU</application> build lacks X11 and >+ <option>-nographic</option> or <option>-curses</option> >+ is not an available option. <option>-vnc</option> works best with ...Something missing after `option'? >+ an en-us keymap on the host. >+ Use the port <filename role="package">net/tightvnc</filename> >+ with <application>QEMU</application>. The X keymap on the host >+ can be changed temporarily using <command>setxkbmap</command>, >+ see the manual pages for more information.</para> >+ </note> >+ </sect3> >+ >+ <sect3 id="virtualization-host-qemu-linuxguest"> >+ <title>&linux; guest examples</title> >+ >+ <para>As an example, we run the well known <ulink >+ url="http://knoppix.net">Knoppix</ulink>; &linux; live-CD/DVD in qemu:</para> >+ >+ <screen>&prompt.user; <userinput>qemu -m 256 -cdrom KNOPPIX_V5.3.1DVD-2008-03-26-EN.iso -boot d -monitor stdio -soundhw es1370</userinput></screen> >+ >+ <para>In this example we launched <application>QEMU</application> >+ with an ES1370 sound card enabled for the guest OS.</para> >+ >+ <para>Click into the guest window to access the guest >+ mouse pointer and hit <keycombo action="simul"><keycap>Alt</keycap> >+ <keycap>Ctrl</keycap></keycombo> to leave the guest window >+ mouse grab.</para> >+ >+ <note> >+ <para>Debian/Ubuntu (and their offsprings) have a record of >+ shipping partially broken <application>QEMU</application> >+ bioses, so if you have problems using a packaged >+ <application>QEMU</application> these distros also try ...on these distros? >+ using the bios found in that <application>QEMU</application> >+ version's source tarball (<filename>pc-bios/bios.bin</filename> >+ in there) instead of the one installed by your distro >+ package.</para> >+ </note> >+ </sect3> >+ >+ <sect3 id="virtualization-host-qemu-tuntap"> >+ <title>Simple Example for using <application>QEMU</application> >+ tuntap networking on &os; Hosts</title> >+ >+ <para>In cases where you want a <application>QEMU</application> >+ guest to appear as a seperate (virtual) host on your network, >+ or when you are on an amd64 host where the default usermode >+ networking doesn't quite work, or when you are simply concerned >+ about virtual network performance, you may want to use tuntap >+ networking.</para> >+ >+ <para>The idea here is to have <application>QEMU</application> >+ talk to a &man.tap.4; interface, which bridge with your host's >+ physical interface, and that <application>QEMU</application> >+ then passes the traffic of the emulated NIC that the guest >+ uses on. Since you don't want to run <application>QEMU</application> >+ as root you first need to setup permissions on the tap device in >+ &man.devfs.conf.5; so that <application>QEMU</application> >+ running as your user can acess it. For example add:</para> >+ >+ <programlisting>own tap0 <replaceable><username or uid></replaceable></programlisting> >+ >+ <para>Next figure out two IPs in an unused sub-subnet of your >+ host's network, one for the tap interface and the other for the >+ guest (this is important so the host itself can talk to the guest's >+ emulated nic properly), and then edit qemu's tuntap setup script >+ that gets executed after qemu opens a tap device, >+ <filename>/usr/local/etc/qemu-ifup</filename> to read something >+ like this:</para> >+ >+ <programlisting>#!/bin/sh >+sudo /sbin/ifconfig $1 <replaceable><IP for the tap interface></replaceable> netmask <replaceable><sub-subnet's netmask></replaceable> >+case "`/sbin/ifconfig bridge0`" in >+ *" $1 "*) ;; # already in the bridge >+ *) sudo /sbin/ifconfig bridge0 addm $1 ;; >+esac</programlisting> >+ >+ <para>sudo is in ports as >+ <filename role="package">security/sudo</filename>, if your user >+ is in the wheel group you can add the following line to >+ <filename>/usr/local/etc/sudoers</filename>:</para> >+ >+ <programlisting>%wheel ALL=/sbin/ifconfig</programlisting> >+ >+ <para>Then load the kernel modules <filename>if_tap.ko</filename> and >+ <filename>if_bridge.ko</filename>, restart devfs, set the >+ <varname>net.link.tap.user_open</varname> sysctl, create >+ the bridge and add your host's physical interface to it:</para> >+ >+ <screen>&prompt.root; <userinput>kldload if_tap if_bridge</userinput> >+&prompt.root; <userinput>/etc/rc.d/devfs restart</userinput> >+&prompt.root; <userinput>sysctl net.link.tap.user_open=1</userinput> >+&prompt.root; <userinput>ifconfig bridge0 create</userinput> >+&prompt.root; <userinput>ifconfig bridge0 addm <replaceable><host's physical interface></replaceable> up</userinput></screen> >+ >+ <para>Now start the <application>QEMU</application>:</para> >+ >+ <screen>&prompt.user; <userinput>qemu -m 256 -hda guest.img -boot c -net nic -net tap,ifname=tap0</userinput></screen> >+ >+ <para>Then configure the NIC in the guest like >+ other hosts on your physical network.</para> >+ >+ <note> >+ <para>If you have more than one <application>QEMU</application> >+ guest on a network you need to make sure they use different >+ MAC addresses, the MAC address can be set via >+ <option>-net nic,macaddr</option>.</para> >+ </note> >+ >+ <para>To make the settings permanent, add the following lines >+ in <filename>/boot/loader.conf</filename>:</para> >+ >+ <programlisting>if_tap_load="YES" >+if_bridge_load="YES"</programlisting> >+ >+ <para>Add the following line in <filename>/etc/sysctl.conf</filename>:</para> >+ >+ <programlisting>net.link.tap.user_open=1</programlisting> >+ >+ <para>And add the bridge configuration in <filename>/etc/rc.conf</filename>:</para> >+ >+ <programlisting>cloned_interfaces="bridge0" >+ifconfig_bridge0="addm <replaceable><host's physical interface></replaceable> up"</programlisting> >+ </sect3> >+ >+ <sect3 id="virtualization-host-qemu-help"> >+ <title>User Documentation and Resources</title> >+ >+ <para>The <application>QEMU</application> package >+ includes qemu(1) man page and the following locally installed html >+ documents:</para> >+ >+ <itemizedlist> >+ <listitem><para><filename>/usr/local/share/doc/qemu/qemu-doc.html</filename></para></listitem> >+ <listitem><para><filename>/usr/local/share/doc/qemu/qemu-tech.html</filename></para></listitem> >+ </itemizedlist> >+ >+ <para>Places to check other than the official documentation:</para> >+ >+ <itemizedlist> >+ <listitem> >+ <para><filename role="package">emulators/qemu-devel</filename> >+ <ulink url="http://www.freebsd.org/cgi/cvsweb.cgi/ports/emulators/qemu-devel/pkg-message">; >+ pkg-message</ulink></para> >+ </listitem> Well actually you want the pkg-message of the qemu port you are using, i.e. emulators/qemu/pkg-message when you are using that, they can differ slightly. (like, atm kqemu only works for qemu-system-x86_64 on amd64 hosts with emulators/qemu, while with qemu-devel it also works for the 32 bit `qemu'.) Oh and also cvsweb can be wrong when you are running an old version of the port, like when someone pkg_add -r 's release packages, so maybe better just stick with `pkg_info -D qemu\* |less' as I had it. >+ <listitem> >+ <para>The <ulink >+ url="http://lists.freebsd.org/pipermail/freebsd-emulation/">; >+ freebsd-emulation mailing list archive</ulink>.</para> >+ </listitem> >+ <listitem> >+ <para>The <ulink >+ url="http://qemu-forum.ipi.fi/">; >+ qemu forum</ulink> >+ has howtos, patches, and code snapshots. Note, however >+ that the qemu sources won't build on &os; without some changes.</para> >+ </listitem> >+ <listitem> >+ <para>The <ulink >+ url="http://lists.gnu.org/archive/html/qemu-devel/">; >+ qemu-devel mailing list archive</ulink>.</para> >+ </listitem> >+ </itemizedlist> >+ </sect2> > </sect1> > > </chapter> Ok that seems to be it for now. Thanx, Juergen
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200812211651.mBLGpLd5005216>