ADMIN

Management
Chef
at the same time and get in each
other’s way.
Role-Out
To group multiple cookbooks in a
role, create a new file below Roles in
the repository, say, beispiel.rb, with
the following content:
name "beispiel"
description "Example of a role"
run_list("recipe[emacs]", U
"recipe[zsh]", "recipe[git]")
This groups the emacs, zsh and git
recipes under the beispiel role name.
Then send the role to the server like
this:
Figure 2: The web front end login page: the default password specified on the right is incorrect.
Changing the slightly cryptic default
after logging in the first time is a good
idea.
Now go to the Nodes menu. When
you get there, click the client name,
change to the Edit tab, and finally
drag the recipe you want to use from
Available Recipes and drop it into
the Run List (the recipe will slot into
the top position in the list). In the
example, you would now see emacs
at the top [Figure 3]. To store this assignment,
press the Save Node button
bottom left on the page.
Client-side now, manually launch the
chef-client tool:
sudo chef‐client
This command line immediately
opens a server connection, picks
up the recipes assigned to the client
(only emacs for the time being) and
executes the recipes [Figure 5]. To allow
this to happen on a regular basis,
you should run the client at regular
intervals as a daemon:
chef‐client ‐i 3600 ‐s 600
In this example, the client contacts
the server every 3,600 seconds. The
-s parameter lets you vary the period
slightly. If you don’t set this, all of
your clients might query the server
rake roles
In the web front end, you can assign
roles to a node just like cookbooks
using drag and drop.
Freshly Stirred
Ready-made recipes and cookbooks
off the Internet will only cover standard
application cases. For special
cases, or individual configurations,
you will typically need to create your
own cookbook.
The following, extremely simple
example, creates a text file on the client
called /​tmp/​thoughts.txt that is
based on the quick_start cookbook
[6], and it adds a sentence that is
G Figure 4: The Status tab lists all the nodes with their last contact attempts
and recipe assignments (following Run List).
F Figure 3: Using drag and drop to assign recipes to a node. In this example, the
client runs the beispiel recipe first, followed by emacs.
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