--- /dev/null
+Ganeti installation tutorial
+============================
+
+Documents Ganeti version 2.0.
+
+.. contents::
+
+Introduction
+------------
+
+Ganeti is a cluster virtualization management system based on Xen or
+KVM. This document explains how to bootstrap a Ganeti node (Xen
+*dom0*), create a running cluster and install virtual instance (Xen
+*domU*). You need to repeat most of the steps in this document for
+every node you want to install, but of course we recommend creating
+some semi-automatic procedure if you plan to deploy Ganeti on a
+medium/large scale.
+
+A basic Ganeti terminology glossary is provided in the introductory
+section of the *Ganeti administrator's guide*. Please refer to that
+document if you are uncertain about the terms we are using.
+
+Ganeti has been developed for Linux and is distribution-agnostic.
+This documentation will use Debian Lenny as an example system but the
+examples can easily be translated to any other distribution. ou are
+expected to be familiar with your distribution, its package management
+system, and Xen or KVM before trying to use Ganeti.
+
+This document is divided into two main sections:
+
+- Installation of the base system and base components
+
+- Configuration of the environment for Ganeti
+
+Each of these is divided into sub-sections. While a full Ganeti system
+will need all of the steps specified, some are not strictly required
+for every environment. Which ones they are, and why, is specified in
+the corresponding sections.
+
+Installing the base system and base components
+----------------------------------------------
+
+Hardware requirements
++++++++++++++++++++++
+
+Any system supported by your Linux distribution is fine. 64-bit
+systems are better as they can support more memory.
+
+Any disk drive recognized by Linux (``IDE``/``SCSI``/``SATA``/etc.)
+is supported in Ganeti. Note that no shared storage (e.g. ``SAN``) is
+needed to get high-availability features (but of course, one can be
+used to store the images). It is highly recommended to use more than
+one disk drive to improve speed. But Ganeti also works with one disk
+per machine.
+
+Installing the base system
+++++++++++++++++++++++++++
+
+**Mandatory** on all nodes.
+
+It is advised to start with a clean, minimal install of the operating
+system. The only requirement you need to be aware of at this stage is
+to partition leaving enough space for a big (**minimum** 20GiB) LVM
+volume group which will then host your instance filesystems, if you
+want to use all Ganeti features. The volume group name Ganeti 2.0 uses
+(by default) is ``xenvg``.
+
+You can also use file-based storage only, without LVM, but this setup
+is not detailed in this document.
+
+
+While you can use an existing system, please note that the Ganeti
+installation is intrusive in terms of changes to the system
+configuration, and it's best to use a newly-installed system without
+important data on it.
+
+Also, for best results, it's advised that the nodes have as much as
+possible the same hardware and software configuration. This will make
+administration much easier.
+
+Hostname issues
+~~~~~~~~~~~~~~~
+
+Note that Ganeti requires the hostnames of the systems (i.e. what the
+``hostname`` command outputs to be a fully-qualified name, not a short
+name. In other words, you should use *node1.example.com* as a hostname
+and not just *node1*.
+
+.. admonition:: Debian
+
+ Debian Lenny and Etch configures the hostname differently than you
+ need it for Ganeti. For example, this is what Etch puts in
+ ``/etc/hosts`` in certain situations::
+
+ 127.0.0.1 localhost
+ 127.0.1.1 node1.example.com node1
+
+ but for Ganeti you need to have::
+
+ 127.0.0.1 localhost
+ 192.168.1.1 node1.example.com node1
+
+ replacing ``192.168.1.1`` with your node's address. Also, the file
+ ``/etc/hostname`` which configures the hostname of the system
+ should contain ``node1.example.com`` and not just ``node1`` (you
+ need to run the command ``/etc/init.d/hostname.sh start`` after
+ changing the file).
+
+Installing Xen
+++++++++++++++
+
+**Mandatory** on all nodes.
+
+While Ganeti is developed with the ability to modularly run on
+different virtualization environments in mind the only two currently
+useable on a live system are Xen and KVM. Supported
+Xen versions are: 3.0.3, 3.0.4 and 3.1.
+
+Please follow your distribution's recommended way to install and set
+up Xen, or install Xen from the upstream source, if you wish,
+following their manual. For KVM, make sure you have a KVM-enabled
+kernel and the KVM tools.
+
+After installing either hypervisor, you need to reboot into your new
+system. On some distributions this might involve configuring GRUB
+appropriately, whereas others will configure it automatically when you
+install the respective kernels.
+
+.. admonition:: Debian
+
+ Under Lenny or Etch you can install the relevant
+ ``xen-linux-system`` package, which will pull in both the
+ hypervisor and the relevant kernel. Also, if you are installing a
+ 32-bit Lenny/Etch, you should install the ``libc6-xen`` package
+ (run ``apt-get install libc6-xen``).
+
+Xen settings
+~~~~~~~~~~~~
+
+It's recommended that dom0 is restricted to a low amount of memory
+(512MiB or 1GiB is reasonable) and that memory ballooning is disabled
+in the file ``/etc/xen/xend-config.sxp`` by setting
+the value ``dom0-min-mem`` to 0,
+like this::
+
+ (dom0-min-mem 0)
+
+For optimum performance when running both CPU and I/O intensive
+instances, it's also recommended that the dom0 is restricted to one
+CPU only, for example by booting with the kernel parameter ``nosmp``.
+
+It is recommended that you disable xen's automatic save of virtual
+machines at system shutdown and subsequent restore of them at reboot.
+To obtain this make sure the variable ``XENDOMAINS_SAVE`` in the file
+``/etc/default/xendomains`` is set to an empty value.
+
+.. admonition:: Debian
+
+ Besides the ballooning change which you need to set in
+ ``/etc/xen/xend-config.sxp``, you need to set the memory and nosmp
+ parameters in the file ``/boot/grub/menu.lst``. You need to modify
+ the variable ``xenhopt`` to add ``dom0_mem=1024M`` like this::
+
+ ## Xen hypervisor options to use with the default Xen boot option
+ # xenhopt=dom0_mem=1024M
+
+ and the ``xenkopt`` needs to include the ``nosmp`` option like
+ this::
+
+ ## Xen Linux kernel options to use with the default Xen boot option
+ # xenkopt=nosmp
+
+ Any existing parameters can be left in place: it's ok to have
+ ``xenkopt=console=tty0 nosmp``, for example. After modifying the
+ files, you need to run::
+
+ /sbin/update-grub
+
+If you want to run HVM instances too with Ganeti and want VNC access
+to the console of your instances, set the following two entries in
+``/etc/xen/xend-config.sxp``::
+
+ (vnc-listen '0.0.0.0') (vncpasswd '')
+
+You need to restart the Xen daemon for these settings to take effect::
+
+ /etc/init.d/xend restart
+
+Selecting the instance kernel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+After you have installed Xen, you need to tell Ganeti exactly what
+kernel to use for the instances it will create. This is done by
+creating a symlink from your actual kernel to
+``/boot/vmlinuz-2.6-xenU``, and one from your initrd
+to ``/boot/initrd-2.6-xenU``. Note that if you don't
+use an initrd for the domU kernel, you don't need
+to create the initrd symlink.
+
+.. admonition:: Debian
+
+ After installation of the ``xen-linux-system`` package, you need to
+ run (replace the exact version number with the one you have)::
+
+ cd /boot
+ ln -s vmlinuz-2.6.26-1-xen-amd64 vmlinuz-2.6-xenU
+ ln -s initrd.img-2.6.26-1-xen-amd64 initrd-2.6-xenU
+
+Installing DRBD
++++++++++++++++
+
+Recommended on all nodes: DRBD_ is required if you want to use the
+high availability (HA) features of Ganeti, but optional if you don't
+require HA or only run Ganeti on single-node clusters. You can upgrade
+a non-HA cluster to an HA one later, but you might need to export and
+re-import all your instances to take advantage of the new features.
+
+.. _DRBD: http://www.drbd.org/
+
+Supported DRBD versions: 8.0.x. It's recommended to have at least
+version 8.0.12.
+
+Now the bad news: unless your distribution already provides it
+installing DRBD might involve recompiling your kernel or anyway
+fiddling with it. Hopefully at least the Xen-ified kernel source to
+start from will be provided.
+
+The good news is that you don't need to configure DRBD at all. Ganeti
+will do it for you for every instance you set up. If you have the
+DRBD utils installed and the module in your kernel you're fine. Please
+check that your system is configured to load the module at every boot,
+and that it passes the following option to the module
+``minor_count=255``. This will allow you to use up to 128 instances
+per node (for most clusters 128 should be enough, though).
+
+.. admonition:: Debian
+
+ On Debian, you can just install (build) the DRBD 8.0.x module with
+ the following commands (make sure you are running the Xen kernel)::
+
+ apt-get install drbd8-source drbd8-utils
+ m-a update
+ m-a a-i drbd8
+ echo drbd minor_count=128 >> /etc/modules
+ depmod -a
+ modprobe drbd minor_count=128
+
+ It is also recommended that you comment out the default resources
+ in the ``/etc/drbd.conf`` file, so that the init script doesn't try
+ to configure any drbd devices. You can do this by prefixing all
+ *resource* lines in the file with the keyword *skip*, like this::
+
+ skip resource r0 {
+ ...
+ }
+
+ skip resource "r1" {
+ ...
+ }
+
+Other required software
++++++++++++++++++++++++
+
+Besides Xen and DRBD, you will need to install the following (on all
+nodes):
+
+- LVM version 2, `<http://sourceware.org/lvm2/>`_
+
+- OpenSSL, `<http://www.openssl.org/>`_
+
+- OpenSSH, `<http://www.openssh.com/portable.html>`_
+
+- bridge utilities, `<http://bridge.sourceforge.net/>`_
+
+- iproute2, `<http://developer.osdl.org/dev/iproute2>`_
+
+- arping (part of iputils package),
+ `<ftp://ftp.inr.ac.ru/ip-routing/iputils-current.tar.gz>`_
+
+- Python version 2.4 or 2.5, `<http://www.python.org>`_
+
+- Python OpenSSL bindings, `<http://pyopenssl.sourceforge.net/>`_
+
+
+- simplejson Python module, `<http://www.undefined.org/python/#simplejson>`_
+
+- pyparsing Python module, `<http://pyparsing.wikispaces.com/>`_
+
+These programs are supplied as part of most Linux distributions, so
+usually they can be installed via apt or similar methods. Also many of
+them will already be installed on a standard machine.
+
+
+.. admonition:: Debian
+
+ You can use this command line to install all needed packages::
+
+ # apt-get install lvm2 ssh bridge-utils iproute iputils-arping \
+ python python-pyopenssl openssl python-pyparsing python-simplejson
+
+Setting up the environment for Ganeti
+-------------------------------------
+
+Configuring the network
++++++++++++++++++++++++
+
+**Mandatory** on all nodes.
+
+Ganeti relies on Xen running in "bridge mode", which means the
+instances network interfaces will be attached to a software bridge
+running in dom0. Xen by default creates such a bridge at startup, but
+your distribution might have a different way to do things.
+
+Beware that the default name Ganeti uses is ``xen-br0`` (which was
+used in Xen 2.0) while Xen 3.0 uses ``xenbr0`` by default. The default
+bridge your Ganeti cluster will use for new instances can be specified
+at cluster initialization time.
+
+.. admonition:: Debian
+
+ The recommended way to configure the Xen bridge is to edit your
+ ``/etc/network/interfaces`` file and substitute your normal
+ Ethernet stanza with the following snippet::
+
+ auto xen-br0
+ iface xen-br0 inet static
+ address YOUR_IP_ADDRESS
+ netmask YOUR_NETMASK
+ network YOUR_NETWORK
+ broadcast YOUR_BROADCAST_ADDRESS
+ gateway YOUR_GATEWAY
+ bridge_ports eth0
+ bridge_stp off
+ bridge_fd 0
+
+The following commands need to be executed on the local console:
+
+ ifdown eth0
+ ifup xen-br0
+
+To check if the bridge is setup, use the ``ip`` and ``brctl show``
+commands::
+
+ # ip a show xen-br0
+ 9: xen-br0: <BROADCAST,MULTICAST,UP,10000> mtu 1500 qdisc noqueue
+ link/ether 00:20:fc:1e:d5:5d brd ff:ff:ff:ff:ff:ff
+ inet 10.1.1.200/24 brd 10.1.1.255 scope global xen-br0
+ inet6 fe80::220:fcff:fe1e:d55d/64 scope link
+ valid_lft forever preferred_lft forever
+
+ # brctl show xen-br0
+ bridge name bridge id STP enabled interfaces
+ xen-br0 8000.0020fc1ed55d no eth0
+
+Configuring LVM
++++++++++++++++
+
+**Mandatory** on all nodes.
+
+The volume group is required to be at least 20GiB.
+
+If you haven't configured your LVM volume group at install time you
+need to do it before trying to initialize the Ganeti cluster. This is
+done by formatting the devices/partitions you want to use for it and
+then adding them to the relevant volume group::
+
+ pvcreate /dev/sda3
+ vgcreate xenvg /dev/sda3
+
+or::
+
+ pvcreate /dev/sdb1
+ pvcreate /dev/sdc1
+ vgcreate xenvg /dev/sdb1 /dev/sdc1
+
+If you want to add a device later you can do so with the *vgextend*
+command::
+
+ pvcreate /dev/sdd1
+ vgextend xenvg /dev/sdd1
+
+Optional: it is recommended to configure LVM not to scan the DRBD
+devices for physical volumes. This can be accomplished by editing
+``/etc/lvm/lvm.conf`` and adding the
+``/dev/drbd[0-9]+`` regular expression to the
+``filter`` variable, like this::
+
+ filter = ["r|/dev/cdrom|", "r|/dev/drbd[0-9]+|" ]
+
+Installing Ganeti
++++++++++++++++++
+
+**Mandatory** on all nodes.
+
+It's now time to install the Ganeti software itself. Download the
+source from the project page at `<http://code.google.com/p/ganeti/>`_,
+and install it (replace 2.0.0 with the latest version)::
+
+ tar xvzf ganeti-2.0.0.tar.gz
+ cd ganeti-2.0.0
+ ./configure --localstatedir=/var --sysconfdir=/etc
+ make
+ make install
+ mkdir /srv/ganeti/ /srv/ganeti/os /srv/ganeti/export
+
+You also need to copy the file
+``doc/examples/ganeti.initd`` from the source archive
+to ``/etc/init.d/ganeti`` and register it with your
+distribution's startup scripts, for example in Debian::
+
+ update-rc.d ganeti defaults 20 80
+
+In order to automatically restart failed instances, you need to setup
+a cron job run the *ganeti-watcher* command. A sample cron file is
+provided in the source at ``doc/examples/ganeti.cron`` and you can
+copy that (eventually altering the path) to ``/etc/cron.d/ganeti``.
+
+Installing the Operating System support packages
+++++++++++++++++++++++++++++++++++++++++++++++++
+
+**Mandatory** on all nodes.
+
+To be able to install instances you need to have an Operating System
+installation script. An example OS that works under Debian and can
+install Debian and Ubuntu instace OSes is provided on the project web
+site. Download it from the project page and follow the instructions
+in the ``README`` file. Here is the installation procedure (replace
+0.7 with the latest version that is compatible with your ganeti
+version)::
+
+ cd /usr/local/src/
+ wget http://ganeti.googlecode.com/files/ganeti-instance-debootstrap-0.7.tar.gz
+ tar xzf ganeti-instance-debootstrap-0.7.tar.gz
+ cd ganeti-instance-debootstrap-0.7
+ ./configure
+ make
+ make install
+
+In order to use this OS definition, you need to have internet access
+from your nodes and have the *debootstrap*, *dump* and *restore*
+commands installed on all nodes. Also, if the OS is configured to
+partition the instance's disk in
+``/etc/default/ganeti-instance-debootstrap``, you will need *kpartx*
+installed.
+
+.. admonition:: Debian
+
+ Use this command on all nodes to install the required packages::
+
+ apt-get install debootstrap dump kpartx
+
+Alternatively, you can create your own OS definitions. See the manpage
+*ganeti-os-interface*.
+
+Initializing the cluster
+++++++++++++++++++++++++
+
+**Mandatory** on one node per cluster.
+
+The last step is to initialize the cluster. After you've repeated the
+above process on all of your nodes, choose one as the master, and
+execute::
+
+ gnt-cluster init <CLUSTERNAME>
+
+The *CLUSTERNAME* is a hostname, which must be resolvable (e.g. it
+must exist in DNS or in ``/etc/hosts``) by all the nodes in the
+cluster. You must choose a name different from any of the nodes names
+for a multi-node cluster. In general the best choice is to have a
+unique name for a cluster, even if it consists of only one machine, as
+you will be able to expand it later without any problems. Please note
+that the hostname used for this must resolve to an IP address reserved
+**exclusively** for this purpose, and cannot be the name of the first
+(master) node.
+
+If the bridge name you are using is not ``xen-br0``, use the *-b
+<BRIDGENAME>* option to specify the bridge name. In this case, you
+should also use the *--master-netdev <BRIDGENAME>* option with the
+same BRIDGENAME argument.
+
+You can use a different name than ``xenvg`` for the volume group (but
+note that the name must be identical on all nodes). In this case you
+need to specify it by passing the *-g <VGNAME>* option to
+``gnt-cluster init``.
+
+To set up the cluster as an HVM cluster, use the
+``--enabled-hypervisors=xen-hvm`` option to enable the HVM hypervisor
+(you can also add ``,xen-pvm`` to enable the PVM one too). You will
+also need to create the VNC cluster password file
+``/etc/ganeti/vnc-cluster-password`` which contains one line with the
+default VNC password for the cluster.
+
+To setup the cluster for KVM-only usage (KVM and Xen cannot be mixed),
+pass ``--enabled-hypervisors=kvm`` to the init command.
+
+You can also invoke the command with the ``--help`` option in order to
+see all the possibilities.
+
+Joining the nodes to the cluster
+++++++++++++++++++++++++++++++++
+
+**Mandatory** for all the other nodes.
+
+After you have initialized your cluster you need to join the other
+nodes to it. You can do so by executing the following command on the
+master node::
+
+ gnt-node add <NODENAME>
+
+Separate replication network
+++++++++++++++++++++++++++++
+
+**Optional**
+
+Ganeti uses DRBD to mirror the disk of the virtual instances between
+nodes. To use a dedicated network interface for this (in order to
+improve performance or to enhance security) you need to configure an
+additional interface for each node. Use the *-s* option with
+``gnt-cluster init`` and ``gnt-node add`` to specify the IP address of
+this secondary interface to use for each node. Note that if you
+specified this option at cluster setup time, you must afterwards use
+it for every node add operation.
+
+Testing the setup
++++++++++++++++++
+
+Execute the ``gnt-node list`` command to see all nodes in the
+cluster::
+
+ # gnt-node list
+ Node DTotal DFree MTotal MNode MFree Pinst Sinst
+ node1.example.com 197404 197404 2047 1896 125 0 0
+
+Setting up and managing virtual instances
+-----------------------------------------
+
+Setting up virtual instances
+++++++++++++++++++++++++++++
+
+This step shows how to setup a virtual instance with either
+non-mirrored disks (``plain``) or with network mirrored disks
+(``drbd``). All commands need to be executed on the Ganeti master
+node (the one on which ``gnt-cluster init`` was run). Verify that the
+OS scripts are present on all cluster nodes with ``gnt-os list``.
+
+
+To create a virtual instance, you need a hostname which is resolvable
+(DNS or ``/etc/hosts`` on all nodes). The following command will
+create a non-mirrored instance for you::
+
+ gnt-instance add -t plain -s 1G -n node1 -o debootstrap instance1.example.com
+ * creating instance disks...
+ adding instance instance1.example.com to cluster config
+ - INFO: Waiting for instance instance1.example.com to sync disks.
+ - INFO: Instance instance1.example.com's disks are in sync.
+ creating os for instance instance1.example.com on node node1.example.com
+ * running the instance OS create scripts...
+ * starting instance...
+
+The above instance will have no network interface enabled. You can
+access it over the virtual console with ``gnt-instance console
+inst1``. There is no password for root. As this is a Debian instance,
+you can modify the ``/etc/network/interfaces`` file to setup the
+network interface (eth0 is the name of the interface provided to the
+instance).
+
+To create a network mirrored instance, change the argument to the *-t*
+option from ``plain`` to ``drbd`` and specify the node on which the
+mirror should reside with the second value of the *--node* option,
+like this (note that the command output includes timestamps which have
+been removed for clarity)::
+
+ # gnt-instance add -t drbd -s 1G -n node1:node2 -o debootstrap instance2
+ * creating instance disks...
+ adding instance instance2.example.com to cluster config
+ - INFO: Waiting for instance instance2.example.com to sync disks.
+ - INFO: - device disk/0: 35.50% done, 11 estimated seconds remaining
+ - INFO: - device disk/0: 100.00% done, 0 estimated seconds remaining
+ - INFO: Instance instance2.example.com's disks are in sync.
+ creating os for instance instance2.example.com on node node1.example.com
+ * running the instance OS create scripts...
+ * starting instance...
+
+Managing virtual instances
+++++++++++++++++++++++++++
+
+All commands need to be executed on the Ganeti master node.
+
+To access the console of an instance, run::
+
+ gnt-instance console INSTANCENAME
+
+To shutdown an instance, run::
+
+ gnt-instance shutdown INSTANCENAME
+
+To startup an instance, run::
+
+ gnt-instance startup INSTANCENAME
+
+To failover an instance to its secondary node (only possible with
+``drbd`` disk templates), run::
+
+ gnt-instance failover INSTANCENAME
+
+For more instance and cluster administration details, see the
+*Ganeti administrator's guide*.
+++ /dev/null
-<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V4.2//EN" [
-]>
- <article class="specification">
- <articleinfo>
- <title>Ganeti installation tutorial</title>
- </articleinfo>
- <para>Documents Ganeti version 2.0</para>
-
- <sect1>
- <title>Introduction</title>
-
- <para>
- Ganeti is a cluster virtualization management system based on
- Xen or KVM. This document explains how to bootstrap a Ganeti
- node (Xen <literal>dom0</literal>), create a running cluster and
- install virtual instance (Xen <literal>domU</literal>). You
- need to repeat most of the steps in this document for every node
- you want to install, but of course we recommend creating some
- semi-automatic procedure if you plan to deploy Ganeti on a
- medium/large scale.
- </para>
-
- <para>
- A basic Ganeti terminology glossary is provided in the
- introductory section of the <emphasis>Ganeti administrator's
- guide</emphasis>. Please refer to that document if you are
- uncertain about the terms we are using.
- </para>
-
- <para>
- Ganeti has been developed for Linux and is
- distribution-agnostic. This documentation will use Debian Lenny
- as an example system but the examples can easily be translated
- to any other distribution. You are expected to be familiar with
- your distribution, its package management system, and Xen or KVM
- before trying to use Ganeti.
- </para>
-
- <para>This document is divided into two main sections:
-
- <itemizedlist>
- <listitem>
- <simpara>Installation of the base system and base
- components</simpara>
- </listitem>
- <listitem>
- <simpara>Configuration of the environment for
- Ganeti</simpara>
- </listitem>
- </itemizedlist>
-
- Each of these is divided into sub-sections. While a full Ganeti system
- will need all of the steps specified, some are not strictly required for
- every environment. Which ones they are, and why, is specified in the
- corresponding sections.
- </para>
-
- </sect1>
-
- <sect1>
- <title>Installing the base system and base components</title>
-
- <sect2>
- <title>Hardware requirements</title>
-
- <para>
- Any system supported by your Linux distribution is fine. 64-bit
- systems are better as they can support more memory.
- </para>
-
- <para>
- Any disk drive recognized by Linux
- (<literal>IDE</literal>/<literal>SCSI</literal>/<literal>SATA</literal>/etc.)
- is supported in Ganeti. Note that no shared storage (e.g.
- <literal>SAN</literal>) is needed to get high-availability features. It
- is highly recommended to use more than one disk drive to improve speed.
- But Ganeti also works with one disk per machine.
- </para>
-
- <sect2>
- <title>Installing the base system</title>
-
- <para>
- <emphasis role="strong">Mandatory</emphasis> on all nodes.
- </para>
-
- <para>
- It is advised to start with a clean, minimal install of the
- operating system. The only requirement you need to be aware of
- at this stage is to partition leaving enough space for a big
- (<emphasis role="strong">minimum
- <constant>20GiB</constant></emphasis>) LVM volume group which
- will then host your instance filesystems, if you want to use
- all Ganeti features. The volume group name Ganeti 2.0 uses (by
- default) is <emphasis>xenvg</emphasis>.
- </para>
-
- <para>
- You can also use file-based storage only, without LVM, but
- this is not detailed in this document.
- </para>
-
- <para>
- While you can use an existing system, please note that the
- Ganeti installation is intrusive in terms of changes to the
- system configuration, and it's best to use a newly-installed
- system without important data on it.
- </para>
-
- <para>
- Also, for best results, it's advised that the nodes have as
- much as possible the same hardware and software
- configuration. This will make administration much easier.
- </para>
-
- <sect3>
- <title>Hostname issues</title>
- <para>
- Note that Ganeti requires the hostnames of the systems
- (i.e. what the <computeroutput>hostname</computeroutput>
- command outputs to be a fully-qualified name, not a short
- name. In other words, you should use
- <literal>node1.example.com</literal> as a hostname and not
- just <literal>node1</literal>.
- </para>
-
- <formalpara>
- <title>Debian</title>
- <para>
- Note that Debian Lenny configures the hostname differently
- than you need it for Ganeti. For example, this is what
- Etch puts in <filename>/etc/hosts</filename> in certain
- situations:
-<screen>
-127.0.0.1 localhost
-127.0.1.1 node1.example.com node1
-</screen>
-
- but for Ganeti you need to have:
-<screen>
-127.0.0.1 localhost
-192.168.1.1 node1.example.com node1
-</screen>
- replacing <literal>192.168.1.1</literal> with your node's
- address. Also, the file <filename>/etc/hostname</filename>
- which configures the hostname of the system should contain
- <literal>node1.example.com</literal> and not just
- <literal>node1</literal> (you need to run the command
- <computeroutput>/etc/init.d/hostname.sh
- start</computeroutput> after changing the file).
- </para>
- </formalpara>
- </sect3>
-
- </sect2>
-
- <sect2>
- <title>Installing Xen</title>
-
- <para>
- <emphasis role="strong">Mandatory</emphasis> on all nodes.
- </para>
-
- <para>
- While Ganeti is developed with the ability to modularly run on
- different virtualization environments in mind the only two
- currently useable on a live system are <ulink
- url="http://xen.xensource.com/">Xen</ulink> and KVM. Supported
- versions are: <simplelist type="inline">
- <member><literal>3.0.3</literal></member>
- <member><literal>3.0.4</literal></member>
- <member><literal>3.1</literal></member> </simplelist>.
- </para>
-
- <para>
- Please follow your distribution's recommended way to install
- and set up Xen, or install Xen from the upstream source, if
- you wish, following their manual. For KVM, make sure you have
- a KVM-enabled kernel and the KVM tools.
- </para>
-
- <para>
- After installing either hypervisor, you need to reboot into
- your new system. On some distributions this might involve
- configuring GRUB appropriately, whereas others will configure
- it automatically when you install the respective kernels.
- </para>
-
- <formalpara><title>Debian</title>
- <para>
- Under Debian Lenny or Etch you can install the relevant
- <literal>xen-linux-system</literal> package, which will pull
- in both the hypervisor and the relevant kernel. Also, if you
- are installing a 32-bit Lenny/Etch, you should install the
- <computeroutput>libc6-xen</computeroutput> package (run
- <computeroutput>apt-get install libc6-xen</computeroutput>).
- </para>
- </formalpara>
-
- <sect3>
- <title>Xen settings</title>
-
- <para>
- It's recommended that dom0 is restricted to a low amount of
- memory (<constant>512MiB</constant> or
- <constant>1GiB</constant> is reasonable) and that memory
- ballooning is disabled in the file
- <filename>/etc/xen/xend-config.sxp</filename> by setting the
- value <literal>dom0-min-mem</literal> to
- <constant>0</constant>, like this:
- <computeroutput>(dom0-min-mem 0)</computeroutput>
- </para>
-
- <para>
- For optimum performance when running both CPU and I/O
- intensive instances, it's also recommended that the dom0 is
- restricted to one CPU only, for example by booting with the
- kernel parameter <literal>nosmp</literal>.
- </para>
-
- <para>
- It is recommended that you disable xen's automatic save of virtual
- machines at system shutdown and subsequent restore of them at reboot.
- To obtain this make sure the variable
- <literal>XENDOMAINS_SAVE</literal> in the file
- <literal>/etc/default/xendomains</literal> is set to an empty value.
- </para>
-
- <formalpara>
- <title>Debian</title>
- <para>
- Besides the ballooning change which you need to set in
- <filename>/etc/xen/xend-config.sxp</filename>, you need to
- set the memory and nosmp parameters in the file
- <filename>/boot/grub/menu.lst</filename>. You need to
- modify the variable <literal>xenhopt</literal> to add
- <userinput>dom0_mem=1024M</userinput> like this:
-<screen>
-## Xen hypervisor options to use with the default Xen boot option
-# xenhopt=dom0_mem=1024M
-</screen>
- and the <literal>xenkopt</literal> needs to include the
- <userinput>nosmp</userinput> option like this:
-<screen>
-## Xen Linux kernel options to use with the default Xen boot option
-# xenkopt=nosmp
-</screen>
-
- Any existing parameters can be left in place: it's ok to
- have <computeroutput>xenkopt=console=tty0
- nosmp</computeroutput>, for example. After modifying the
- files, you need to run:
-<screen>
-/sbin/update-grub
-</screen>
- </para>
- </formalpara>
- <para>
- If you want to run HVM instances too with Ganeti and want
- VNC access to the console of your instances, set the
- following two entries in
- <filename>/etc/xen/xend-config.sxp</filename>:
-<screen>
-(vnc-listen '0.0.0.0')
-(vncpasswd '')
-</screen>
- You need to restart the Xen daemon for these settings to
- take effect:
-<screen>
-/etc/init.d/xend restart
-</screen>
- </para>
-
- </sect3>
-
- <sect3>
- <title>Selecting the instance kernel</title>
-
- <para>
- After you have installed Xen, you need to tell Ganeti
- exactly what kernel to use for the instances it will
- create. This is done by creating a
- <emphasis>symlink</emphasis> from your actual kernel to
- <filename>/boot/vmlinuz-2.6-xenU</filename>, and one from
- your initrd to
- <filename>/boot/initrd-2.6-xenU</filename>. Note that if you
- don't use an initrd for the <literal>domU</literal> kernel,
- you don't need to create the initrd symlink.
- </para>
-
- <formalpara>
- <title>Debian</title>
- <para>
- After installation of the
- <literal>xen-linux-system</literal> package, you need to
- run (replace the exact version number with the one you
- have):
- <screen>
-cd /boot
-ln -s vmlinuz-2.6.18-5-xen-686 vmlinuz-2.6-xenU
-ln -s initrd.img-2.6.18-5-xen-686 initrd-2.6-xenU
- </screen>
- </para>
- </formalpara>
- </sect3>
-
- </sect2>
-
- <sect2>
- <title>Installing DRBD</title>
-
- <para>
- Recommended on all nodes: <ulink
- url="http://www.drbd.org/">DRBD</ulink> is required if you
- want to use the high availability (HA) features of Ganeti, but
- optional if you don't require HA or only run Ganeti on
- single-node clusters. You can upgrade a non-HA cluster to an
- HA one later, but you might need to export and re-import all
- your instances to take advantage of the new features.
- </para>
-
- <para>
- Supported DRBD versions: <literal>8.0.x</literal>.
- It's recommended to have at least version <literal>8.0.12</literal>.
- </para>
-
- <para>
- Now the bad news: unless your distribution already provides it
- installing DRBD might involve recompiling your kernel or
- anyway fiddling with it. Hopefully at least the Xen-ified
- kernel source to start from will be provided.
- </para>
-
- <para>
- The good news is that you don't need to configure DRBD at all.
- Ganeti will do it for you for every instance you set up. If
- you have the DRBD utils installed and the module in your
- kernel you're fine. Please check that your system is
- configured to load the module at every boot, and that it
- passes the following option to the module
- <computeroutput>minor_count=255</computeroutput>. This will
- allow you to use up to 128 instances per node (for most clusters
- <constant>128 </constant> should be enough, though).
- </para>
-
- <formalpara><title>Debian</title>
- <para>
- You can just install (build) the DRBD 8.0.x module with the
- following commands (make sure you are running the Xen
- kernel):
- </para>
- </formalpara>
-
- <screen>
-apt-get install drbd8-source drbd8-utils
-m-a update
-m-a a-i drbd8
-echo drbd minor_count=128 >> /etc/modules
-depmod -a
-modprobe drbd minor_count=128
- </screen>
-
- <para>
- It is also recommended that you comment out the default
- resources in the <filename>/etc/drbd.conf</filename> file, so
- that the init script doesn't try to configure any drbd
- devices. You can do this by prefixing all
- <literal>resource</literal> lines in the file with the keyword
- <literal>skip</literal>, like this:
- </para>
-
- <screen>
-skip resource r0 {
-...
-}
-
-skip resource "r1" {
-...
-}
- </screen>
-
- </sect2>
-
- <sect2>
- <title>Other required software</title>
-
- <para>Besides Xen and DRBD, you will need to install the
- following (on all nodes):</para>
-
- <itemizedlist>
- <listitem>
- <simpara><ulink url="http://sourceware.org/lvm2/">LVM
- version 2</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="http://www.openssl.org/">OpenSSL</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="http://www.openssh.com/portable.html">OpenSSH</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink url="http://bridge.sourceforge.net/">Bridge
- utilities</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="http://developer.osdl.org/dev/iproute2">iproute2</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="ftp://ftp.inr.ac.ru/ip-routing/iputils-current.tar.gz">arping</ulink>
- (part of iputils package)</simpara>
- </listitem>
- <listitem>
- <simpara><ulink url="http://www.python.org">Python 2.4</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="http://pyopenssl.sourceforge.net/">Python OpenSSL
- bindings</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="http://www.undefined.org/python/#simplejson">simplejson Python
- module</ulink></simpara>
- </listitem>
- <listitem>
- <simpara><ulink
- url="http://pyparsing.wikispaces.com/">pyparsing Python
- module</ulink></simpara>
- </listitem>
- </itemizedlist>
-
- <para>
- These programs are supplied as part of most Linux
- distributions, so usually they can be installed via apt or
- similar methods. Also many of them will already be installed
- on a standard machine.
- </para>
-
-
- <formalpara><title>Debian</title>
-
- <para>You can use this command line to install all of them:</para>
-
- </formalpara>
- <screen>
-# apt-get install lvm2 ssh bridge-utils iproute iputils-arping \
- python python-pyopenssl openssl python-pyparsing python-simplejson
- </screen>
-
- </sect2>
-
- </sect1>
-
-
- <sect1>
- <title>Setting up the environment for Ganeti</title>
-
- <sect2>
- <title>Configuring the network</title>
-
- <para><emphasis role="strong">Mandatory</emphasis> on all nodes.</para>
-
- <para>
- Ganeti relies on Xen running in "bridge mode", which means the
- instances network interfaces will be attached to a software bridge
- running in dom0. Xen by default creates such a bridge at startup, but
- your distribution might have a different way to do things.
- </para>
-
- <para>
- Beware that the default name Ganeti uses is
- <hardware>xen-br0</hardware> (which was used in Xen 2.0)
- while Xen 3.0 uses <hardware>xenbr0</hardware> by
- default. The default bridge your Ganeti cluster will use for new
- instances can be specified at cluster initialization time.
- </para>
-
- <formalpara><title>Debian</title>
- <para>
- The recommended Debian way to configure the Xen bridge is to
- edit your <filename>/etc/network/interfaces</filename> file
- and substitute your normal Ethernet stanza with the
- following snippet:
-
- <screen>
-auto xen-br0
-iface xen-br0 inet static
- address <replaceable>YOUR_IP_ADDRESS</replaceable>
- netmask <replaceable>YOUR_NETMASK</replaceable>
- network <replaceable>YOUR_NETWORK</replaceable>
- broadcast <replaceable>YOUR_BROADCAST_ADDRESS</replaceable>
- gateway <replaceable>YOUR_GATEWAY</replaceable>
- bridge_ports eth0
- bridge_stp off
- bridge_fd 0
- </screen>
- </para>
- </formalpara>
-
- <para>
-The following commands need to be executed on the local console
- </para>
- <screen>
-ifdown eth0
-ifup xen-br0
- </screen>
-
- <para>
- To check if the bridge is setup, use <command>ip</command>
- and <command>brctl show</command>:
- <para>
-
- <screen>
-# ip a show xen-br0
-9: xen-br0: <BROADCAST,MULTICAST,UP,10000> mtu 1500 qdisc noqueue
- link/ether 00:20:fc:1e:d5:5d brd ff:ff:ff:ff:ff:ff
- inet 10.1.1.200/24 brd 10.1.1.255 scope global xen-br0
- inet6 fe80::220:fcff:fe1e:d55d/64 scope link
- valid_lft forever preferred_lft forever
-
-# brctl show xen-br0
-bridge name bridge id STP enabled interfaces
-xen-br0 8000.0020fc1ed55d no eth0
- </screen>
-
-
- </sect2>
-
- <sect2>
- <title>Configuring LVM</title>
-
-
- <para><emphasis role="strong">Mandatory</emphasis> on all nodes.</para>
-
- <note>
- <simpara>The volume group is required to be at least
- <constant>20GiB</constant>.</simpara>
- </note>
- <para>
- If you haven't configured your LVM volume group at install
- time you need to do it before trying to initialize the Ganeti
- cluster. This is done by formatting the devices/partitions you
- want to use for it and then adding them to the relevant volume
- group:
-
- <screen>
-pvcreate /dev/sda3
-vgcreate xenvg /dev/sda3
- </screen>
-or
- <screen>
-pvcreate /dev/sdb1
-pvcreate /dev/sdc1
-vgcreate xenvg /dev/sdb1 /dev/sdc1
- </screen>
- </para>
-
- <para>
- If you want to add a device later you can do so with the
- <citerefentry><refentrytitle>vgextend</refentrytitle>
- <manvolnum>8</manvolnum></citerefentry> command:
- </para>
-
- <screen>
-pvcreate /dev/sdd1
-vgextend xenvg /dev/sdd1
- </screen>
-
- <formalpara>
- <title>Optional</title>
- <para>
- It is recommended to configure LVM not to scan the DRBD
- devices for physical volumes. This can be accomplished by
- editing <filename>/etc/lvm/lvm.conf</filename> and adding
- the <literal>/dev/drbd[0-9]+</literal> regular expression to
- the <literal>filter</literal> variable, like this:
-<screen>
- filter = [ "r|/dev/cdrom|", "r|/dev/drbd[0-9]+|" ]
-</screen>
- </para>
- </formalpara>
-
- </sect2>
-
- <sect2>
- <title>Installing Ganeti</title>
-
- <para><emphasis role="strong">Mandatory</emphasis> on all nodes.</para>
-
- <para>
- It's now time to install the Ganeti software itself. Download
- the source from <ulink
- url="http://code.google.com/p/ganeti/"></ulink>.
- </para>
-
- <screen>
-tar xvzf ganeti-@GANETI_VERSION@.tar.gz
-cd ganeti-@GANETI_VERSION@
-./configure --localstatedir=/var --sysconfdir=/etc
-make
-make install
-mkdir /srv/ganeti/ /srv/ganeti/os /srv/ganeti/export
- </screen>
-
- <para>
- You also need to copy the file
- <filename>doc/examples/ganeti.initd</filename>
- from the source archive to
- <filename>/etc/init.d/ganeti</filename> and register it with
- your distribution's startup scripts, for example in Debian:
- </para>
- <screen>update-rc.d ganeti defaults 20 80</screen>
-
- <para>
- In order to automatically restart failed instances, you need
- to setup a cron job run the
- <computeroutput>ganeti-watcher</computeroutput> program. A
- sample cron file is provided in the source at
- <filename>doc/examples/ganeti.cron</filename> and you can
- copy that (eventually altering the path) to
- <filename>/etc/cron.d/ganeti</filename>
- </para>
-
- </sect2>
-
- <sect2>
- <title>Installing the Operating System support packages</title>
-
- <para><emphasis role="strong">Mandatory</emphasis> on all nodes.</para>
-
- <para>
- To be able to install instances you need to have an Operating
- System installation script. An example OS that works under
- Debian and can install Debian and Ubuntu instace OSes is
- provided on the project web site. Download it from <ulink
- url="http://code.google.com/p/ganeti/"></ulink> and follow the
- instructions in the <filename>README</filename> file. Here is
- the installation procedure (replace <constant>0.7</constant>
- with the latest version that is compatible with your ganeti
- version):
- </para>
-
- <screen>
-cd /usr/local/src/
-wget http://ganeti.googlecode.com/files/ganeti-instance-debootstrap-0.7.tar.gz
-tar xzf ganeti-instance-debootstrap-0.7.tar.gz
-cd ganeti-instance-debootstrap-0.7
-./configure
-make
-make install
- </screen>
-
- <para>
- In order to use this OS definition, you need to have internet
- access from your nodes and have the <citerefentry>
- <refentrytitle>debootstrap</refentrytitle>
- <manvolnum>8</manvolnum></citerefentry>, <citerefentry>
- <refentrytitle>dump</refentrytitle><manvolnum>8</manvolnum>
- </citerefentry> and <citerefentry>
- <refentrytitle>restore</refentrytitle>
- <manvolnum>8</manvolnum> </citerefentry> commands installed on
- all nodes. Also, if the OS is configured to partition the
- instance's disk in
- <filename>/etc/default/ganeti-instance-debootstrap</filename>,
- you will need <command>kpartx</command> installed.
- </para>
- <formalpara>
- <title>Debian</title>
- <para>
- Use this command on all nodes to install the required
- packages:
-
- <screen>apt-get install debootstrap dump kpartx</screen>
- </para>
- </formalpara>
-
- <para>
- Alternatively, you can create your own OS definitions. See the
- manpage
- <citerefentry>
- <refentrytitle>ganeti-os-interface</refentrytitle>
- <manvolnum>8</manvolnum>
- </citerefentry>.
- </para>
-
- </sect2>
-
- <sect2>
- <title>Initializing the cluster</title>
-
- <para><emphasis role="strong">Mandatory:</emphasis> only on one
- node per cluster.</para>
-
-
- <para>
- The last step is to initialize the cluster. After you've
- repeated the above process on all of your nodes, choose one as
- the master, and execute:
- </para>
-
- <screen>
-gnt-cluster init <replaceable>CLUSTERNAME</replaceable>
- </screen>
-
- <para>
- The <replaceable>CLUSTERNAME</replaceable> is a hostname,
- which must be resolvable (e.g. it must exist in DNS or in
- <filename>/etc/hosts</filename>) by all the nodes in the
- cluster. You must choose a name different from any of the
- nodes names for a multi-node cluster. In general the best
- choice is to have a unique name for a cluster, even if it
- consists of only one machine, as you will be able to expand it
- later without any problems. Please note that the hostname used
- for this must resolve to an IP address reserved <emphasis
- role="strong">exclusively</emphasis> for this purpose.
- </para>
-
- <para>
- If the bridge name you are using is not
- <literal>xen-br0</literal>, use the <option>-b
- <replaceable>BRIDGENAME</replaceable></option> option to
- specify the bridge name. In this case, you should also use the
- <option>--master-netdev
- <replaceable>BRIDGENAME</replaceable></option> option with the
- same <replaceable>BRIDGENAME</replaceable> argument.
- </para>
-
- <para>
- You can use a different name than <literal>xenvg</literal> for
- the volume group (but note that the name must be identical on
- all nodes). In this case you need to specify it by passing the
- <option>-g <replaceable>VGNAME</replaceable></option> option
- to <computeroutput>gnt-cluster init</computeroutput>.
- </para>
-
- <para>
- To set up the cluster as an HVM cluster, use the
- <option>--enabled-hypervisors=xen-hvm</option> option to
- enable the HVM hypervisor (you can also add
- <userinput>,xen-pvm</userinput> to enable the PVM one
- too). You will also need to create the VNC cluster password
- file <filename>/etc/ganeti/vnc-cluster-password</filename>
- which contains one line with the default VNC password for the
- cluster.
- </para>
-
- <para>
- To setup the cluster for KVM-only usage (KVM and Xen cannot be
- mixed), pass <option>--enabled-hypervisors=kvm</option> to the
- init command.
- </para>
-
- <para>
- You can also invoke the command with the
- <option>--help</option> option in order to see all the
- possibilities.
- </para>
-
- </sect2>
-
- <sect2>
- <title>Joining the nodes to the cluster</title>
-
- <para>
- <emphasis role="strong">Mandatory:</emphasis> for all the
- other nodes.
- </para>
-
- <para>
- After you have initialized your cluster you need to join the
- other nodes to it. You can do so by executing the following
- command on the master node:
- </para>
- <screen>
-gnt-node add <replaceable>NODENAME</replaceable>
- </screen>
- </sect2>
-
- <sect2>
- <title>Separate replication network</title>
-
- <para><emphasis role="strong">Optional</emphasis></para>
- <para>
- Ganeti uses DRBD to mirror the disk of the virtual instances
- between nodes. To use a dedicated network interface for this
- (in order to improve performance or to enhance security) you
- need to configure an additional interface for each node. Use
- the <option>-s</option> option with
- <computeroutput>gnt-cluster init</computeroutput> and
- <computeroutput>gnt-node add</computeroutput> to specify the
- IP address of this secondary interface to use for each
- node. Note that if you specified this option at cluster setup
- time, you must afterwards use it for every node add operation.
- </para>
- </sect2>
-
- <sect2>
- <title>Testing the setup</title>
-
- <para>
- Execute the <computeroutput>gnt-node list</computeroutput>
- command to see all nodes in the cluster:
- <screen>
-# gnt-node list
-Node DTotal DFree MTotal MNode MFree Pinst Sinst
-node1.example.com 197404 197404 2047 1896 125 0 0
- </screen>
- </para>
- </sect2>
-
- <sect1>
- <title>Setting up and managing virtual instances</title>
- <sect2>
- <title>Setting up virtual instances</title>
- <para>
- This step shows how to setup a virtual instance with either
- non-mirrored disks (<computeroutput>plain</computeroutput>) or
- with network mirrored disks
- (<computeroutput>drbd</computeroutput>). All
- commands need to be executed on the Ganeti master node (the
- one on which <computeroutput>gnt-cluster init</computeroutput>
- was run). Verify that the OS scripts are present on all
- cluster nodes with <computeroutput>gnt-os
- list</computeroutput>.
- </para>
- <para>
- To create a virtual instance, you need a hostname which is
- resolvable (DNS or <filename>/etc/hosts</filename> on all
- nodes). The following command will create a non-mirrored
- instance for you:
- </para>
- <screen>
-gnt-instance add --node=node1 -o debootstrap -t plain inst1.example.com
-* creating instance disks...
-adding instance inst1.example.com to cluster config
-Waiting for instance inst1.example.com to sync disks.
-Instance inst1.example.com's disks are in sync.
-creating os for instance inst1.example.com on node node1.example.com
-* running the instance OS create scripts...
- </screen>
-
- <para>
- The above instance will have no network interface enabled.
- You can access it over the virtual console with
- <computeroutput>gnt-instance console
- <literal>inst1</literal></computeroutput>. There is no
- password for root. As this is a Debian instance, you can
- modify the <filename>/etc/network/interfaces</filename> file
- to setup the network interface (<literal>eth0</literal> is the
- name of the interface provided to the instance).
- </para>
-
- <para>
- To create a network mirrored instance, change the argument to
- the <option>-t</option> option from <literal>plain</literal>
- to <literal>drbd</literal> and specify the node on
- which the mirror should reside with the second value of the
- <option>--node</option> option, like this:
- </para>
-
- <screen>
-# gnt-instance add -t drbd -n node1:node2 -o debootstrap instance2
-* creating instance disks...
-adding instance instance2 to cluster config
-Waiting for instance instance1 to sync disks.
-- device sdb: 3.50% done, 304 estimated seconds remaining
-- device sdb: 21.70% done, 270 estimated seconds remaining
-- device sdb: 39.80% done, 247 estimated seconds remaining
-- device sdb: 58.10% done, 121 estimated seconds remaining
-- device sdb: 76.30% done, 72 estimated seconds remaining
-- device sdb: 94.80% done, 18 estimated seconds remaining
-Instance instance2's disks are in sync.
-creating os for instance instance2 on node node1.example.com
-* running the instance OS create scripts...
-* starting instance...
- </screen>
-
- </sect2>
-
- <sect2>
- <title>Managing virtual instances</title>
- <para>
- All commands need to be executed on the Ganeti master node
- </para>
-
- <para>
- To access the console of an instance, use
- <computeroutput>gnt-instance console
- <replaceable>INSTANCENAME</replaceable></computeroutput>.
- </para>
-
- <para>
- To shutdown an instance, use <computeroutput>gnt-instance
- shutdown
- <replaceable>INSTANCENAME</replaceable></computeroutput>. To
- startup an instance, use <computeroutput>gnt-instance startup
- <replaceable>INSTANCENAME</replaceable></computeroutput>.
- </para>
-
- <para>
- To failover an instance to its secondary node (only possible
- with <literal>drbd</literal> disk templates), use
- <computeroutput>gnt-instance failover
- <replaceable>INSTANCENAME</replaceable></computeroutput>.
- </para>
-
- <para>
- For more instance and cluster administration details, see the
- <emphasis>Ganeti administrator's guide</emphasis>.
- </para>
-
- </sect2>
-
- </sect1>
-
- </article>
projects / ganeti-local / commitdiff