1 <!doctype refentry PUBLIC "-//OASIS//DTD DocBook V4.1//EN" [
3 <!-- Fill in your name for FIRSTNAME and SURNAME. -->
4 <!-- Please adjust the date whenever revising the manpage. -->
5 <!ENTITY dhdate "<date>June 08, 2010</date>">
6 <!-- SECTION should be 1-8, maybe w/ subsection other parameters are
7 allowed: see man(7), man(1). -->
8 <!ENTITY dhsection "<manvolnum>7</manvolnum>">
9 <!ENTITY dhucpackage "<refentrytitle>ganeti</refentrytitle>">
10 <!ENTITY dhpackage "ganeti">
12 <!ENTITY debian "<productname>Debian</productname>">
13 <!ENTITY gnu "<acronym>GNU</acronym>">
14 <!ENTITY gpl "&gnu; <acronym>GPL</acronym>">
15 <!ENTITY footer SYSTEM "footer.sgml">
26 <holder>Google Inc.</holder>
34 <refmiscinfo>Ganeti 2.2</refmiscinfo>
37 <refname>&dhpackage;</refname>
39 <refpurpose>cluster-based virtualization management</refpurpose>
44 # gnt-cluster init cluster1.example.com
45 # gnt-node add node2.example.com
46 # gnt-instance add -n node2.example.com \
47 > -o debootstrap --disk 0:size=30g \
48 > -t plain instance1.example.com
52 <title>DESCRIPTION</title>
55 The Ganeti software manages physical nodes and virtual instances
56 of a cluster based on a virtualization software. The current
57 version (2.2) supports Xen 3.x and KVM (72 or above) as hypervisors.
62 <title>Quick start</title>
65 First you must install the software on all the cluster nodes,
66 either from sources or (if available) from a package. The next
67 step is to create the initial cluster configuration, using
68 <userinput>gnt-cluster init</userinput>.
72 Then you can add other nodes, or start creating instances.
78 <title>Cluster architecture</title>
81 In Ganeti 2.0, the architecture of the cluster is a little more
82 complicated than in 1.2. The cluster is coordinated by a master
83 daemon (<citerefentry>
84 <refentrytitle>ganeti-masterd</refentrytitle>
85 <manvolnum>8</manvolnum> </citerefentry>), running on the master
86 node. Each node runs (as before) a node daemon, and the master
87 has the <acronym>RAPI</acronym> daemon running too.
91 <title>Node roles</title>
93 <para>Each node can be in one of the following states:
99 Only one node per cluster can be in this role, and
100 this node is the one holding the authoritative copy of
101 the cluster configuration and the one that can
102 actually execute commands on the cluster and modify
103 the cluster state. See more details under
104 <emphasis>Cluster configuration</emphasis>.
109 <term>master_candidate</term>
111 <para>The node receives the full cluster configuration
112 (configuration file and jobs) and can become a master
113 via the <command>gnt-cluster master-failover</command>
114 command. Nodes that are not in this state cannot
115 transition into the master role due to missing
122 <para>This the normal state of a node.</para>
128 <para>Nodes in this state are functioning normally but
129 cannot receive new instance, because the intention is to
130 set them to <emphasis>offline</emphasis> or remove them
131 from the cluster.</para>
137 <para>These nodes are still recorded in the Ganeti
138 configuration, but except for the master daemon startup
139 voting procedure, they are not actually contacted by the
140 master. This state was added in order to allow broken
141 machines (that are being repaired) to remain in the
142 cluster but without creating problems.</para>
150 <title>Node flags</title>
152 <para>Nodes have two flags which govern which roles they can take:
155 <term>master_capable</term>
158 The node can become a master candidate, and
159 furthermore the master node. When this flag is
160 disabled, the node cannot become a candidate; this can
161 be useful for special networking cases, or less
167 <term>vm_capable</term>
170 The node can host instances. When enabled (the default
171 state), the node will participate in instance
172 allocation, capacity calculation, etc. When disabled,
173 the node will be skipped in many cluster checks and
183 <title>Cluster configuration</title>
185 <para>The master node keeps and is responsible for the cluster
186 configuration. On the filesystem, this is stored under the
188 class="directory">@LOCALSTATEDIR@/ganeti/lib</filename>
189 directory, and if the master daemon is stopped it can be backed
192 <para>The master daemon will replicate the configuration
193 database called <filename>config.data</filename> and the job
194 files to all the nodes in the master candidate role. It will
195 also distribute a copy of some configuration values via the
196 <emphasis>ssconf</emphasis> files, which are stored in the same
197 directory and start with <filename>ssconf_</filename> prefix, to
206 All cluster modification are done via jobs. A job consists of
207 one or more opcodes, and the list of opcodes is processed
208 serially. If an opcode fails, the entire job is failed and
209 later opcodes are no longer processed. A job can be in one of
210 the following states:
215 <simpara>The job has been submitted but not yet
216 processed by the master daemon.</simpara>
222 <simpara>The job is waiting for for locks before the
223 first of its opcodes.</simpara>
227 <term>canceling</term>
229 <para>The job is waiting for locks, but is has been
230 marked for cancellation. It will not transition to
231 <emphasis>running</emphasis>, but to
232 <emphasis>canceled</emphasis>.
239 <simpara>The job is currently being executed.</simpara>
243 <term>canceled</term>
245 <para>The job has been canceled before starting
252 <para>The job has finished successfully.</para>
258 <para>The job has failed during runtime, or the master
259 daemon has been stopped during the job execution.</para>
268 <title>Common options</title>
271 Many Ganeti commands provide the following options. The availability for
272 a certain command can be checked by calling the command using the
273 <option>--help</option> option.
277 <command>gnt-<replaceable>...</replaceable> <replaceable>command</replaceable></command>
279 <arg>--priority <group choice="req">
287 The <option>--dry-run</option> option can be used to check whether an
288 operation would succeed.
292 The option <option>--priority</option> sets the priority for opcodes
293 submitted by the command.
302 <!-- Keep this comment at the end of the file
307 sgml-minimize-attributes:nil
308 sgml-always-quote-attributes:t
311 sgml-parent-document:nil
312 sgml-default-dtd-file:nil
313 sgml-exposed-tags:nil
314 sgml-local-catalogs:nil
315 sgml-local-ecat-files:nil