[chef] Re: How to trigger up auto configuration upgrade by chef!

[Brad Knowles < >]

On Dec 26, 2011, at 2:40 AM, 

 
 wrote:

>  I am trying chef for its configurtion management features. After building 
> up a system consisted of laptop, server, and client, I wonder if chef a 
> good helper to upgrade a certain configuration item on a batch of nodes 
> automatically. If possible, please provide a guidline how to do this. 
> Should I change the cookbook on server then ssh to each client to run 
> "chef-client" and trigger up the upgrade task? If any reference has come up 
> related with my goal, please help attach them to me. Thanks a lot.

Chef can do pretty much whatever you configure it to do, so it all depends on 
how you configure it.

By default, chef-client should be running every five minutes on each client, 
either as a result of installing and using the chef-client cookbook (which 
keeps a copy of chef-client running as a daemon, which will sleep five 
minutes between runs), or out of a cron job that you set up on each client.

From there, it depends on how you configure the cookbooks and recipes.  If 
you set the default run_action to be "upgrade" instead of "install", then you 
should get each machine automatically upgrading itself within five to ten 
minutes of the updated roles/cookbooks/recipes being uploaded to the 
chef-server.


One of the basic tenets that has been adopted by Chef is There Is More Than 
One Way To Do It, a.k.a., TIMTOWTDI, which is usually pronounced "Tim Toady".

Chef itself is relatively agnostic with regards to how things are done -- 
where you express your opinions on what is the "right" way to do something is 
done in the roles, cookbooks, and recipes that you deploy.

There are the community cookbooks that Opscode supports, available through 
the http://community.opscode.com/cookbooks/ website.  Each of these recipes ;
will be pretty opinionated in regards to how they think a particular task 
should be done.  I would encourage you to browse the community cookbooks and 
to learn as much as you can from them.

-- 
Brad Knowles 
<
 >
SAGE Level IV, Chef Level 0.0.1