juju-core

Merge lp:~mark-mims/juju-core/docs-service-groups into lp:juju-core/docs

  1. docs-service-groups
  2. Merge into docs
Proposed by Mark Mims
Status: Merged
Approved by: Nick Veitch
Approved revision: no longer in the source branch.
Merged at revision: 87
Proposed branch: lp:~mark-mims/juju-core/docs-service-groups
Merge into: lp:juju-core/docs
Diff against target: 303 lines (+276/-1)
3 files modified
htmldocs/charms-service-groups.html (+273/-0)
htmldocs/navigation.html (+1/-0)
htmldocs/navigation.json (+2/-1)
To merge this branch: bzr merge lp:~mark-mims/juju-core/docs-service-groups
Reviewer Review Type Date Requested Status
Jorge Castro (community) Approve
Review via email: mp+183264@code.launchpad.net
To post a comment you must log in.
Revision history for this message
Jorge Castro (jorge) wrote :

LGTM, +1

review: Approve

Preview Diff

[H/L] Next/Prev Comment, [J/K] Next/Prev File, [N/P] Next/Prev Hunk
1=== added file 'htmldocs/charms-service-groups.html'
2--- htmldocs/charms-service-groups.html 1970-01-01 00:00:00 +0000
3+++ htmldocs/charms-service-groups.html 2013-08-30 19:55:54 +0000
4@@ -0,0 +1,273 @@
5+<!DOCTYPE html>
6+<html>
7+ <head>
8+ <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
9+ <title>Juju Documentation - Groups of Services</title>
10+ <link href='https://fonts.googleapis.com/css?family=Ubuntu:400,300,300italic,400italic,700,700italic|Ubuntu+Mono' rel='stylesheet' type='text/css' />
11+ <link rel="stylesheet" type="text/css" media="screen" href="//juju.ubuntu.com/wp-content/themes/juju-website/css/reset.css" />
12+ <link rel="stylesheet" type="text/css" media="screen" href="//juju.ubuntu.com/wp-content/themes/juju-website/css/960.css" />
13+ <link rel="stylesheet" type="text/css" media="screen" href="//juju.ubuntu.com/wp-content/themes/juju-website/css/base.css" />
14+ <link rel="stylesheet" type="text/css" media="screen" href="//juju.ubuntu.com/wp-content/themes/juju-website/css/home-new.css" />
15+ <link rel='stylesheet' id='stacktack-css' href='//juju.ubuntu.com/wp-content/plugins/stacktack/css/stacktack.min.css?ver=3.4.2' type='text/css' media='all' />
16+ <link href="css/main.css?1375975745" rel="stylesheet" type="text/css"/>
17+
18+ <!--[if lt IE 9]>
19+ <script type="text/javascript" src="//html5shim.googlecode.com/svn/trunk/html5.js"></script>
20+ <![endif]-->
21+</head>
22+ <body class="resources">
23+ <header class="global clearfix" role="banner">
24+ <div class="header-navigation">
25+ <div>
26+ <nav role="navigation">
27+ <ul>
28+ <li class="page_item page-item-6"><a href="https://juju.ubuntu.com/">Home</a></li>
29+ <li class="page_item page-item-7"><a href="https://juju.ubuntu.com/get-started/">Get started</a></li>
30+ <li class="page_item page-item-9 current_page_item"><a href="https://juju.ubuntu.com/resources/">Resources</a></li>
31+ <li class="page_item page-item-13"><a href="https://juju.ubuntu.com/community/">Community</a></li>
32+ <li class="page_item page-item-3688"><a href="https://juju.ubuntu.com/charm-store/">Charm Store</a></li>
33+ <li class="page_item page-item-3691"><a href="https://juju.ubuntu.com/events/">Events</a></li>
34+ <li class="page_item page-item-4474"><a href="https://juju.ubuntu.com/charm-championship/">Charm Championship</a></li>
35+ <li class="page_item page-item-4249"><a href="https://juju.ubuntu.com/survey/">Survey</a></li>
36+ <li>
37+ <form id="form-search" method="get" action="https://juju.ubuntu.com/">
38+ <fieldset>
39+ <input id="input-search" type="text" name="s" value="Search" />
40+ </fieldset>
41+ </form>
42+ </li>
43+ </ul>
44+ </nav>
45+ </div>
46+ </div>
47+ <div class="header-content">
48+ <div class="clearfix">
49+ <img src="https://juju.ubuntu.com/wp-content/themes/juju-website/img/arrow-nav.png" width="9" height="5" style="left:455px; display: block;" class="arrow-nav">
50+ <div class="header-navigation-secondary"></div>
51+ <div class="header-image"></div>
52+ <h1>Resources</h1>
53+ <h2>A collection of some of the most important online references for Juju users and developers.</h2>
54+ </div>
55+ </div>
56+</header>
57+
58+ <section id="content" class="container-12">
59+ <div class="grid-12 doc-container">
60+ <div id="navlinks" class="grid-3 doc-navigation">LINKS</div>
61+ <div class="grid-9 doc-content">
62+ <article>
63+
64+
65+<!--Actual docs start here-->
66+
67+ <section id="service-groups">
68+ <h1>Groups of Services</h1>
69+ <p></p>
70+
71+ <p>
72+ Juju deploys units of a service from a charm.
73+ The simplest way to do this is
74+ </p>
75+
76+<pre class="prettyprint">
77+juju deploy mysql
78+</pre>
79+
80+ <p>
81+ which will take the latest version of the mysql charm straight from the store and create a single service unit.
82+ </p>
83+
84+ <p>
85+ By default, juju creates a unit of a service named after the charm... "mysql" in the above example.
86+ </p>
87+
88+ <p>
89+ You can specify the name for the service when deploying
90+ </p>
91+
92+<pre class="prettyprint">
93+juju deploy mysql wikidb
94+</pre>
95+
96+ <p>
97+ which will create a unit of the "wikidb" service.
98+ </p>
99+
100+ <p>
101+ Why specify names for services? The simplest reason is organizational... it let's you stay organized as your infrastructure gets more complex:
102+ </p>
103+
104+<pre class="prettyprint">
105+juju deploy mysql website-db
106+juju deploy mysql app-master-db
107+juju deploy mysql app-slave-db -n2
108+</pre>
109+
110+ <p>
111+ But there're other reasons to do this... namely service groups. Really service groups are nothing other than named services.
112+ They're called out as a separate feature because they're quite useful in a few different ways.
113+ </p>
114+
115+ <h2>Roles</h2>
116+
117+ <p>
118+ Some services acquire a role at runtime based on the relations that are joined.
119+ </p>
120+
121+ <p>
122+ A great example of this is the hadoop charm. It can instantiate services
123+ </p>
124+
125+<pre class="prettyprint">
126+juju deploy hadoop namenode
127+juju deploy hadoop datacluster -n40
128+</pre>
129+
130+ <p>
131+ which are identical at this point except for the service name that juju's using for the various units.
132+ </p>
133+
134+ <p>
135+ The services these acquire roles at relation-time via
136+ </p>
137+
138+<pre class="prettyprint">
139+juju add-relation namenode:namenode datacluster:datanode
140+juju add-relation namenode:jobtracker datacluster:tasktracker
141+</pre>
142+
143+ <p>
144+ The relations determine the service role.
145+ </p>
146+
147+ <p>
148+ Another example of this is mysql replication.
149+ </p>
150+
151+<pre class="prettyprint">
152+juju deploy mysql masterdb
153+juju deploy mysql slavedb -n2
154+</pre>
155+
156+ <p>
157+ where the different services are related to each other
158+ </p>
159+
160+<pre class="prettyprint">
161+juju add-relation masterdb:master slavedb:slave
162+</pre>
163+
164+ <p>
165+ and to other services via
166+ </p>
167+
168+<pre class="prettyprint">
169+juju deploy mediawiki mywiki
170+juju add-relation mywiki:db masterdb:db
171+juju add-relation mywiki:slave slavedb:db
172+</pre>
173+
174+ <h2>Upgrade Groups and/or Config Groups</h2>
175+
176+ <p>
177+ There are also interesting use-cases for breaking large services down into separate groups of units.
178+ Instead of a single 5000-node hadoop service named <em>hadoop-slave</em>, you might build that cluster
179+ from multiple smaller service groups.
180+ </p>
181+
182+<pre class="prettyprint">
183+juju deploy hadoop hadoop-master
184+juju deploy hadoop hadoop-slave-A -n2500
185+juju deploy hadoop hadoop-slave-B -n2500
186+juju add-relation hadoop-master:namenode hadoop-slave-A:datanode
187+juju add-relation hadoop-master:namenode hadoop-slave-B:datanode
188+...
189+</pre>
190+
191+ <p>
192+ These service groups can be managed independently by juju for upgrades and configuration
193+ </p>
194+
195+<pre class="prettyprint">
196+juju set hadoop-slave-B some_param=new_value
197+</pre>
198+
199+ <p>
200+ This technique can potentially be a way juju can manage rolling upgrades for a service.
201+ Of course, this depends heavily on the services in question and how well they support
202+ version management, schema changes, etc.
203+ </p>
204+
205+
206+ </section>
207+
208+ <!--Actual docs end here-->
209+
210+
211+
212+ </article>
213+ </div>
214+ </div>
215+ </section>
216+ <div class="shadow"></div>
217+ <footer class="global clearfix" role="contentinfo">
218+ <div class="row">
219+ <div class="inner-wrapper">
220+ <nav role="navigation" class="clearfix">
221+ <ul class="footer-a">
222+ <li class="grid-3 first-col">
223+ <h4><a href="/get-started">Get started</a></h4>
224+ <ul>
225+ <li class="page_item page-item-20"><a href="https://juju.ubuntu.com/get-started/local/">Local</a></li>
226+ <li class="page_item page-item-22"><a href="https://juju.ubuntu.com/get-started/amazon/">Amazon Web Services</a></li>
227+ <li class="page_item page-item-18"><a href="https://juju.ubuntu.com/get-started/hp-cloud/">HP Cloud</a></li>
228+ <li class="page_item page-item-16"><a href="https://juju.ubuntu.com/get-started/rackspace/">Rackspace</a></li>
229+ <li class="page_item page-item-3596"><a href="https://juju.ubuntu.com/get-started/openstack/">Openstack</a></li>
230+ <li class="page_item page-item-3600"><a href="https://juju.ubuntu.com/get-started/maas/">MAAS</a></li>
231+ </ul>
232+ </li>
233+ <li class="grid-3">
234+ <h4><a href="/resources">Resources</a></h4>
235+ <ul>
236+ <li><a href="http://juju.ubuntu.com/docs">Documentation</a></li>
237+ <li><a href="/resources/videos/">Videos</a></li>
238+ <li><a href="http://uistage.jujucharms.com:8080/">Juju GUI demo site</a></li>
239+ </ul>
240+ </li>
241+ <li class="grid-3">
242+ <h4><a href="/community">Community</a></h4>
243+ <ul>
244+ <li class="page_item page-item-28"><a href="https://juju.ubuntu.com/community/juju-blog/">Juju Blog</a></li>
245+ <li class="page_item page-item-4262"><a href="https://juju.ubuntu.com/community/weekly-charm-meeting/">Weekly Charm Meeting</a></li>
246+ <li class="page_item page-item-4036"><a href="https://juju.ubuntu.com/community/charmers/">Charmers</a></li>
247+ <li><a href="https://lists.ubuntu.com/mailman/listinfo/juju">Mailing List</a></li>
248+ <li><a href="http://webchat.freenode.net/?channels=juju">Chat</a></li>
249+ <li><a href="http://askubuntu.com/questions/tagged/juju?sort=faq&pagesize=50">FAQ</a></li>
250+ </ul>
251+ </li>
252+ <li class="grid-3 last-col">
253+ <h4><a href="https://launchpad.net/juju">Code</a></h4>
254+ <ul>
255+ <li><a href="https://launchpad.net/juju-core">Juju Core</a></li>
256+ <li><a href="https://launchpad.net/charms">Charms</a></li>
257+ </ul>
258+ </li>
259+ </ul>
260+ </nav>
261+ </div>
262+ </div>
263+ <div class="row no-border">
264+ <div class="legal inner-wrapper">
265+ <p>&copy; 2013 Canonical Ltd. Ubuntu and Canonical are registered trademarks of Canonical Ltd.</p>
266+ <p><a href="https://bugs.launchpad.net/juju-website/+filebug">Report a bug on this site</a></p>
267+ </div>
268+ </div>
269+</footer>
270+
271+ <script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
272+ <script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jqueryui/1.8.14/jquery-ui.min.js"></script>
273+ <script src="//d38yea5fb4e2oh.cloudfront.net/jquery.stacktack.min.js"></script>
274+ <script type="text/javascript" src="js/main.js"></script>
275+ <script type="text/javascript" src="http://code.jquery.com/jquery-1.9.1.js"></script>
276+ </body>
277+</html>
278
279=== modified file 'htmldocs/navigation.html'
280--- htmldocs/navigation.html 2013-08-22 13:48:21 +0000
281+++ htmldocs/navigation.html 2013-08-30 19:55:54 +0000
282@@ -17,6 +17,7 @@
283 <li class=" sub"><a href="charms-exposing.html">Exposing Services</a></li>
284 <li class=" sub"><a href="charms-scaling.html">Scaling Services</a></li>
285 <li class=" sub"><a href="charms-destroy.html">Destroying Services</a></li>
286+ <li class=" sub"><a href="charms-service-groups.html">Groups of Services</a></li>
287 </ul>
288 <h1>Charm Authors</h1>
289 <ul>
290
291=== modified file 'htmldocs/navigation.json'
292--- htmldocs/navigation.json 2013-08-16 13:29:42 +0000
293+++ htmldocs/navigation.json 2013-08-30 19:55:54 +0000
294@@ -22,7 +22,8 @@
295 "Service Relationships": "charms-relationships.html",
296 "Exposing Services": "charms-exposing.html",
297 "Scaling Services": "charms-scaling.html",
298- "Destroying Services": "charms-destroy.html"
299+ "Destroying Services": "charms-destroy.html",
300+ "Groups of Services": "charms-service-groups.html"
301 }
302 }
303 },

Subscribers

People subscribed via source and target branches