[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled [[GNU Free Documentation License|/fdl]]."]]"""]] [[!meta title="QEMU Image"]] This page discusses things for [[Unix]] systems, there is a separate page for [[Microsoft_Windows]] systems. See the discussion about [[hurd/running/qemu/writeback_caching]]. [[!toc]] --- # Readily Available Images You can use the following images to give the Hurd a try. ## Debian GNU/Hurd [[!inline pages=hurd/running/debian/qemu_image raw=yes feeds=no]] ## Arch Hurd Live CD [[!inline pages=hurd/running/live_cd raw=yes feeds=no]] ## [[NixOS and GuixSD|Nix]] ## Unofficial Images Note that the following images are unofficial ones: they have been prepared by volunteers and may not have been tested extensively. * [Disk image](http://draketo.de/dateien/hurd/bab-hurd-qemu-2008-10-29.img.tar.bz2) with a short intro on translators. Just start it with `qemu -m 1G -drive cache=writeback,file=disk_image.img`. It should work without any of the configuration below. If you want to know what you can do with it, please have a look at [[its_wikipage|hurd/running/qemu/babhurd_image]]. And when you use it, please [tell me your experience with it](http://draketo.de/contact)! - [[community/weblogs/ArneBab]] --- # What is Needed to create a QEMU image ## Debian Installer Instructions for creating a qemu image from the install CDs from debian installer can be found in the README alongside the d-i Hurd images: --- # KVM acceleration Check if your CPU supports kvm: $ egrep '^flags.*(vmx|svm)' /proc/cpuinfo #### If you don't have hardware support (slow): $ apt install qemu Do not enable kernel-kqemu, as that assumes some particular behavior from the guest kernel, which we are reluctant to artificially add to gnumach. If QEMU with KVM is not available, [[Virtualbox]] reportedly has better performance. #### If you have hardware support (recommended): $ apt install qemu-kvm $ modprobe kvm Intel VTx/VTd: Enable Intel kvm in the BIOS On a HP xw4600 Workstation: F10, Security->System Security; Enable VTx and VTd Check that the kvm module is loaded: $ lsmod|grep kvm kvm_intel 38050 0 kvm 213800 1 kvm_intel $ ls -l /dev/kvm crw-rw----+ 1 root kvm 10, 232 Mar 14 15:02 /dev/kvm Add yourself to the kvm group: $ adduser your_user kvm; logout; login AMD SVM (AMD-V): Enable AMD-V in the BIOS if not enabled. Check that the kvm module is loaded: $ lsmod|grep kvm kvm_amd 31862 0 kvm 214088 1 kvm_amd More info on kvm at: http://www.linux-kvm.org/page/FAQ If your machine supports hardware acceleration, you should really use the kvm variant of qemu, as it speeds things quite a lot. --- # HAP/EPT/NPT acceleration Performance will be yet better if HAP (EPT or NPT) is available: $ grep ept /proc/cpuinfo $ grep npt /proc/cpuinfo --- # Installing Debian/Hurd with QEMU using the Debian installer Note: If you have hardware support, replace the qemu commands below with kvm, e.g. qemu-ing -> kvm-img. First off you will need to create a disk image using `qemu-img`. I have set mine to 4 GiB, although you should be able to get away with less. $ qemu-img create hd0.img 4G Next you will want to start up QEMU and begin the installation process. $ qemu -m 1G -drive cache=writeback,file=hd0.img -cdrom debian-7.0-hurd-i386-NETINST-1.iso -net nic,model=e1000 -net user Now at his point do the regular install using `hd0` as your harddrive. Partition it and install the base system. In the installer make your choice of install option: Default install (or your choice) Language: English Country, territory or area: your_choice Locale: your_choice Note that even if you can set the country and locale, your local keyboard is not yet supported. In case of problems with timezone or locale settings do the following after the installation is completed To get the correct timezone: $ dpkg-reconfigure tzdata To get your locale setting: $ nano /etc/locale.gen $ locale-gen Network: Now configured automatically with dhcp IP address: 10.0.2.15 Netmask: 255.255.0.0 Gateway: 10.0.2.2 Nameserver: 10.0.2.3 Qemu network setup: QEMU VLAN <------> Firewall/DHCP server <-----> Internet | (10.0.2.2) | ----> DNS server (10.0.2.3) | ----> SMB server (10.0.2.4) Partitioning method: Guided (or your choice) Partitioning `/dev/hd0`: All files in one partition. **Important**: Since partman does not yet mount other partitions than / automatically at reboot, it is crucial that you choose this option for now. Once you have finished installing the base system (might take some time) the system is rebooted and next boot will be from the hard disk. Now you are able to log in to your newly installed GNU/Hurd system. ## Running the installed system Starting qemu/qemu-kvm: $ kvm -m 1G -net nic,model=e1000 -net user,hostfwd=tcp::5555-:22 -drive cache=writeback,file=hd0.img -vga vmware vmsvga_value_write: guest runs Linux. Note: See below on port forwarding in the networking section. Note: Using the vmware vga driver is useful for setting up X windows, see [Debian GNU/Hurd](http://www.debian.org/ports/hurd/hurd-install) If you have problems with grub hanging during boot with the vmware vga driver: Disable the graphic boot $ nano /etc/default/grub uncomment GRUB_TERMINAL=console $ /usr/sbin/update-grub ### `qemu: fatal: Trying to execute code outside RAM or ROM at 0x000000010010001e` This is due to a bug in QEMU, where the x86_64 QEMU binary fails to properly truncate addresses in 32-bit mode. Waiting for [[!message-id "1386334344-24620-1-git-send-email-agraf@suse.de"]] to be applied and become generally available, just use the `qemu-system-i386` binary instead. See [[!debbug 719633]] ### A few words about the qemu console During the graphical emulation, you can use the following keys: -f Toggle full screen -u Restore the screen's un-scaled dimensions -n Switch to virtual console 'n'. Standard console mappings are: 1 Target system display 2 Monitor 3 Serial port Toggle mouse and keyboard grab. --- # Transferring Files ## Mounting Disk Image on Host You may wish to mount your disk image on your host system to transfer files. To do this you will first need to find the offset of the partition you wish to mount. # fdisk -ul hd0.img ... 128 heads, 63 sectors/track, 0 cylinders, total 0 sectors Units = sectors of 1 * 512 = 512 bytes Device Boot Start End Blocks Id System hd0.img1 * 63 3515903 1757920+ 83 Linux hd0.img2 3515904 4193279 338688 82 Linux swap / Solaris Now take the number of sectors for the beginning of the partition and multiply it by the sector size. My partition starts at sector 63 and I have a sector size of 512 therefore my offset is 32256. For a start at 2048 the ofsset is 1048576. # mount -o loop,offset=32256 hd0.img /mnt/diskimage ## Having QEMU create *virtual FAT disk images* [Link to the manual](http://www.nongnu.org/qemu/qemu-doc.html#SEC25). QEMU has a facility to create FAT file systems on-the-fly: qemu [...] -hdc fat:[somewhere] The Hurd [[`fatfs`_translator|translator/fatfs]] currently is read-only, but for testing executables (etc.) that is enough. And it is much easier than loop-mounting the file systems images. (Also you don't need `root' rights.) However, note that there is a bug in [[translator/fatfs]]: [[!GNU_Savannah_bug 25961]]. --- # Networking in QEMU Some further notes about [[networking]] and home hints about [[networking/sharing_files]]. ## Internet Access If you just want to access the internet from within QEMU, you can setup pfinet for QEMU's user-networking: # settrans -afgp /servers/socket/2 /hurd/pfinet -i /dev/eth0 -a 10.0.2.15 -g 10.0.2.2 -m 255.255.255.0 # echo "nameserver 10.0.2.3" > /etc/resolv.conf If you are on [[Debian GNU/Hurd|debian]], you can even use [[debian/DHCP]]. To get ssh working: # apt install openssh-server (Similarly for telnet if preferred) (See also .) Outgoing internet connections should just work then. Testing it can be difficult with a minimal installation, but `apt update` should work after you have filled out `/etc/apt/sources.list`. After that you should be able to install other network packages, but note that `ping` doesn't work with QEMU's user-networking stack. If you want to connect from the host system to the Hurd system running in QEMU, you can use port forwarding in QEMU or to setup something more advanced, like bridged networking. #### IRC, freenode, #hurd, 2014-02-12 youpi: also, the problems i had with regard to accessing the debian repository were caused by a qemu bug where, in nat mode, qemu is unable to handle dns requests if the host dns servers are ipv6 ones yes, we've noticed that with a student of mine you may be interested by a patch we submitted to qemu-devel, that adds ipv6 support to -net user :) :) for now i directly change resolv.conf braunr: the issue is that you have only ipv6 nameservers, right? yes there's not much better to do than that (patching resolv.conf inside the guest, or apply the ipv6 patch) This is fixed in qemu 2.6 ## Port Forwarding in QEMU/KVM (In the following we assume we use kvm!) #### Logging in to Hurd from a terminal in your host system This is the recommended way to work with a Command Line Interface (CLI) since all your keyboard and locale settings are preserved. a) with ssh (assuming you have installed openssh-server) $ kvm -m 1G -net nic,model=e1000 -net user,hostfwd=tcp::5555-:22 -drive cache=writeback,file=hd0.img & Logging in to the running Hurd: $ ssh -p5555 localhost Copying files: 1) On your host To Hurd: scp -p -P5555 file localhost: From Hurd: scp -p -P5555 localhost:file . 2) On Hurd To host: scp -p file {10.0.2.2,your_host_ip}: . From host: scp -p {10.0.2.2,your_host_ip}:file . b) with telnet (assuming you have installed a telnet server, like telnetd) $ kvm -m 1G -net nic,model=e1000 -net user,hostfwd=tcp::5556-:23 -drive cache=writeback,file=hurd-install.qemu & Logging in to the running Hurd: $ telnet localhost 5556 c) With the tap interface, see below. ## Bridged Networking ### What is Needed 1. Your Linux kernel will need 802.1d Ethernet Bridging support and TUN/TAP device driver support. 2. You will need to install [bridge-utils](http://bridge.sourceforge.net). ### Setting Up the Host Bridge You need to setup a bridge on the host first. This assumes `eth0` is down. I have modified my hosts network startup scripts to automatically setup a bridge, you may want to do this also. # brctl addbr br0 # ifconfig eth0 0.0.0.0 promisc up # brctl addif br0 eth0 At this point you will need to setup `br0` as you would normally `eth0` (`dhcpcd br0` for example). ### The qemu-ifup Script This script gets called when QEMU starts and will attach the tun device to the bridge. QEMU will look for this file at `/etc/qemu-ifup` and that is where I keep mine. #!/bin/sh sudo ifconfig $1 0.0.0.0 promisc up sudo brctl addif br0 $1 ### Setting up the Network in the Hurd Now it is time to start-up your QEMU Hurd system and get networking going in there. **Important:** Remember you may need to use the `-M isapc` or `-isa` flag if using an older version of the gnumach package. $ qemu -m 1G -drive cache=writeback,file=hd0.img -cdrom debian-K9-hurd-i386-CD1.iso -fda floppy.img -boot a -net nic,model=e1000 -net tap Once you have logged in as `root` run the `pfinet` translator with values that apply to your network. Think of your QEMU client as another computer in your network. # settrans -fgap /servers/socket/2 /hurd/pfinet -i /dev/eth0 -a xxx.xxx.xxx.xxx -g xxx.xxx.xxx.xxx -m xxx.xxx.xxx.xxx That should do it! Do not forget to edit/update `/etc/resolv.conf` to get DNS working. --- # Multiboot See "Linux/Multiboot boot specific" section on QEMU manpage. Get the multiboot modules. Either extract them from the disk image, or, download: $ wget https://cdimage.debian.org/cdimage/ports/latest/hurd-i386/gnumach.gz $ wget https://cdimage.debian.org/cdimage/ports/latest/hurd-i386/ext2fs.static $ wget https://cdimage.debian.org/cdimage/ports/latest/hurd-i386/exec.static Generally, these files need to correspond to the ones in the disk image, so don't forget to keep them up to date. The kernel image needs to be uncompressed (`gunzip gnumach.gz`), as otherwise you'll get told: *qemu: linux kernel too old to load a ram disk*. $ qemu [...] \ > --kernel gnumach \ > --initrd \ > 'ext2fs.static --multiboot-command-line=${kernel-command-line} --host-priv-port=${host-port} --device-master-port=${device-port} --exec-server-task=${exec-task} -T typed device:hd0s1 $(task-create) $(task-resume)',\ > 'exec.static $(exec-task=task-create)' Note that, contrary to [[GRUB]]'s configuration file, you don't specify "`argv[0]`" here, and it's fortunate that neither ext2fs nor exec need a comma on their command line... You can also use `--append [...]`, which will show up in `/proc/cmdline`. Command line above crashes with old qemu versions, for instance qemu 1.1.2 on Debian Wheezy, fixed by upgrading to wheezy-backports currently qemu 1.7.0, see [[!debbug 741873]] --- # Related Links These are links that users may find helpful. Debian [[debian/after_install]] -- good source of information pertaining to your system after installation. [[Image_for_L4]] -- a QEMU image for the Hurd/L4 project. [Hurd Installation Guide from eyeside.net](https://web.archive.org/web/20130516025306/http://www.eyeside.net/index.htm)