= Getting started with virtualization ''' [IMPORTANT] ====== This page was automatically converted from https://fedoraproject.org/wiki/Getting_started_with_virtualization It is probably * Badly formatted * Missing graphics and tables that do not covert well from mediawiki * Out-of-date * In need of other love Please fix it, remove this notice, and then add to `_topic_map.yml` Pull requests accepted at https://pagure.io/fedora-docs/fedora-howto Once that is live, go to the original wiki page and add an `{{old}}` tag, followed by a note like .... {{admon/note|This page has a new home!| This wiki page is no longer maintained. Please find the up-to-date version at: https://docs.fedoraproject.org/whatever-the-url }} .... ====== ''' This page deals with using Fedora to host virtual guests. For information the different virtualization technologies available in Fedora, see the link:Tools/Virtualization[dedicated page]. [[using-virtualization-on-fedora]] Using virtualization on Fedora ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fedora uses the libvirt family of tools as its virtualization solution. By default libvirt on Fedora will use Qemu to run guest instances. For information on other virtualization platforms, refer to http://virt.kernelnewbies.org/TechComparison. Qemu can emulate a host machine in software, or given a CPU with hardware support (see below) can use http://www.linux-kvm.org[KVM] to provide a fast full virtualization. Other virtualization products and packages are available but are not covered by this guide. [[installing-and-configuring-fedora-for-virtualized-guests]] Installing and configuring Fedora For virtualized guests ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This section covers setting up libvirt on your system. After the successful completion of this section you will be able to create virtualized guest operating systems. [[system-requirements]] System requirements ^^^^^^^^^^^^^^^^^^^ The common system requirements for virtualization on Fedora are: * At least 600MB of hard disk storage per guest. A minimal command-line Fedora system requires 600MB of storage. Standard fedora desktop guests require at least 3GB of space. * At least 256MB of RAM per guest plus 256 for the base OS. At least 756MB is recommended for each guest of a modern operating system. A good rule of thumb is to think about how much memory is required for the operating system normally and allocate that much to the virtualized guest. KVM requires a CPU with virtualization extensions, found on most consumer CPUs made in the past couple years. These extensions are called Intel VT or AMD-V. To check whether you have proper CPU support, run the command: .... $ egrep '^flags.*(vmx|svm)' /proc/cpuinfo .... If NOTHING is printed, your system does not support the relevant extensions. You can still use the QEMU/KVM, but the emulator will fall back to software virtualization, which is FAR FAR slower. [[installing-the-virtualization-packages]] Installing the virtualization packages ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ When installing Fedora, the virtualization packages can be installed by selecting *Virtualization* in the Base Group in the installer. (This may http://docs.fedoraproject.org/en-US/Fedora/13/html/Installation_Guide/s1-pkgselection-x86.html[no longer apply to your installation method] though). For existing Fedora installations, QEMU, KVM, and other virtualization tools can be installed by running the following command which installs the virtualization group: [[fedora-22-to-current]] Fedora 22 to current: ~~~~~~~~~~~~~~~~~~~~~ For Fedora 21 or previous installations, replace "dnf" with "yum." Yum is now a deprecated package manager and is replaced by DNF on installations of Fedora 22 and onward. .... su -c "dnf install @virtualization" .... This will install below Mandatory and Default packages. .... $ dnf groupinfo virtualization Group: Virtualisation Group-Id: virtualization Description: These packages provide a virtualisation environment. Mandatory Packages: =virt-install Default Packages: =libvirt-daemon-config-network =libvirt-daemon-kvm =qemu-kvm =virt-manager =virt-viewer Optional Packages: guestfs-browser libguestfs-tools python-libguestfs virt-top .... This will install Mandatory, Default and Optional Packages. .... su -c "dnf group install with-optional virtualization" .... To start the service: .... su -c "systemctl start libvirtd" .... To start the service on boot: .... su -c "systemctl enable libvirtd" .... Verify that the kvm kernel modules were properly loaded: .... $ lsmod | grep kvm kvm_amd 55563 0 kvm 419458 1 kvm_amd .... If that command did not list kvm_intel or kvm_amd, KVM is not properly configured. See link:How_to_debug_Virtualization_problems#Ensuring_system_is_KVM_capable[ Ensuring system is KVM capable] for troubleshooting tips. [[networking-support]] Networking Support ^^^^^^^^^^^^^^^^^^ By default libvirt will create a private network for your guests on the host machine. This private network will use a 192.168.x.x subnet and not be reachable directly from the network the host machine is on, but virtual guests can use the host machine as a gateway and can connect out via it. If you need to provide services on your guests that are reachable via other machines on your host network you can use iptables DNAT rules to forward in specific ports, or you can setup a Bridged env. See the http://wiki.libvirt.org/page/Networking[libvirt networking setup page] for more information on how to setup a Bridged network. [[creating-a-fedora-guest]] Creating a Fedora guest ^^^^^^^^^^^^^^^^^^^^^^^ The installation of Fedora guests using anaconda is supported. The installation can be started on the command line via the `virt-install` program or in the GUI program `virt-manager`. [[creating-a-guest-with-virt-install]] Creating a guest with virt-install ++++++++++++++++++++++++++++++++++ `virt-install` is a command line based tool for creating virtualized guests. Refer to http://virt-tools.org/learning/install-with-command-line/ for understanding how to use this tool. Execute `virt-install --help` for command line help. `virt-install` can use kickstart files, for example `virt-install -x ks=kickstart-file-name.ks`. If graphics were enabled, a VNC window will open and present the graphical installer. If graphics were not enabled, a text installer will appear. Proceed with the fedora installation. [[creating-a-guest-with-virt-manager]] Creating a guest with virt-manager ++++++++++++++++++++++++++++++++++ Start the GUI Virtual Machine Manager by selecting it from the "Applications-->System Tools" menu, or by running the following command: .... su -c "virt-manager" .... If you encounter an error along the lines of "Failed to contact configuration server; some possible causes are that you need to enable TCP/IP networking for ORBit, or you have stale NFS locks due to a system crash", trying running `virt-manager` not as root (without the `su -c`). The GUI will prompt for the root password. 1. Open a connection to a hypervisor by choosing File-->Add connection... 2. Choose "qemu" for KVM, or "Xen" for Xen. 3. Choose "local" or select a method to connect to a remote hypervisor 4. After a connection is opened, click the new icon next to the hypervisor, or right click on the active hypervisor and select "New" (Note - the new icon is going to be improved to make it easier to see) 5. A wizard will present the same questions as appear with the `virt-install` command-line utility (see descriptions above). The wizard assumes that a graphical installation is desired and does not prompt for this option. 6. On the last page of the wizard there is a "Finish" button. When this is clicked, the guest OS is provisioned. After a few moments a VNC window should appear. Proceed with the installation as normal. [[remote-management]] Remote management ^^^^^^^^^^^^^^^^^ The following remote management options are available: * (easiest) If using non-root users via SSH, then setup instructions are at: http://wiki.libvirt.org/page/SSHSetup * If using root for access via SSH, then create SSH keys for root, and use `ssh-agent` and `ssh-add` before launching `virt-manager`. * To use TLS, set up a local certificate authority and issue x509 certs to all servers and clients. For information on configuring this option, refer to http://wiki.libvirt.org/page/TLSSetup. [[guest-system-administration]] Guest system administration ^^^^^^^^^^^^^^^^^^^^^^^^^^^ When the installation of the guest operating system is complete, it can be managed using the GUI `virt-manager` program or on the command line using `virsh`. [[managing-guests-with-virt-manager]] Managing guests with virt-manager +++++++++++++++++++++++++++++++++ Start the Virtual Machine Manager. Virtual Machine Manager is in the "Applications-->System Tools" menu, or execute: .... su -c "virt-manager" .... \{1} If you are not root, you will be prompted to enter the root password. Choose`Run unprivileged` to operate in a read-only non-root mode. * Choose the host you wish to manage and click "Connect" in the "Open Connection" dialog window. * The list of virtual machines is displayed in the main window. Guests that are running will display a ">" icon. Guests that are not running will be greyed out. * To manage a particular guest, double click on it, or right click and select "Open". * A new window for the guest will open that will allow you to use its console, see information about its virtual hardware and start/stop/pause it. For further information about `virt-manager` consult the http://virt-manager.et.redhat.com/[project website] Bugs in the `virt-manager` tool should be reported in http://bugzilla.redhat.com[BugZilla] against the 'virt-manager' component [[managing-guests-with-virsh]] Managing guests with virsh ++++++++++++++++++++++++++ The `virsh` command line utility that allows you to manage virtual machines. Guests can be managed on the command line with the `virsh` utility. The `virsh` utility is built around the libvirt management APIl: * `virsh` has a stable set of commands whose syntax and semantics are preserved across updates to the underlying virtualization platform. * `virsh` can be used as an unprivileged user for read-only operations (e.g. listing domains, listing domain statistics). * `virsh` can manage domains running under Xen, Qemu/KVM, esx or other backends with no perceptible difference to the user To start a virtual machine: .... su -c "virsh create " .... To list the virtual machines currently running: .... su -c "virsh list" .... To list all virtual machines, running or not: .... su -c "virsh list --all" .... To gracefully power off a guest: .... su -c "virsh shutdown " .... To non gracefully power off a guest: .... su -c "virsh destroy " .... To save a snapshot of the machine to a file: .... su -c "virsh save " .... To restore a previously saved snapshot: .... su -c "virsh restore " .... To export the configuration file of a virtual machine: .... su -c "virsh dumpxml