[chef] Re: Re: Re: Using Chef to Configue Autoscaled EC2 Instances

[Edward Sargisson < >]

You don't need such complexity. You can just include the role the node
wants in the user-date you register for auto-scaling.
I believe Ubuntu Oneiric has accepted a patch which makes the
user-data thing work with Chef better. There was an email announcement
about that a few months ago.

Cheers,
Edward

On Thu, Nov 10, 2011 at 10:08 AM, Aaron Abramson
<
 >
 wrote:
> I've thought about this, but haven't put much work into implementing it 
> yet.  So this is more of a concept than anything.
>
> Set up a script listening on a server.  It could be a simple php script, IE 
> http://someurl/script.php
>
> Set up the user-data with a bash script that hits the listener.  (wget -O 
> /dev/null http://someurl/script.php?role=myrole)
>
> The script receives the request, and it knows 2 things, the public hostname 
> of the server making the request, and the "role" it is requesting.  The 
> script makes certain assumptions (username, ssh-key, etc) and then executes 
> a system command, calling "knife bootstrap *server* -r "role[myrole]"
>
> So, if you auto-scale official cannonical ubuntu AMI's, simply have the 
> user-data "ping" your knife listener, and knife then bootstraps the server.
>
> Perhaps such a bootstrap request feature could be built into chef-server?
>
>
> Aaron
>
> On Nov 10, 2011, at 11:55 AM, John Martinez wrote:
>
>>
>> Hello,
>>
>> I agree with you, using knife to provision EC2 instances is not the best 
>> way to do this in autoscaled environments. As a temporary solution, I've 
>> done exactly what you suggest. I pass along a lot of things into 
>> user-data, and specifically, a node's role is one of those. I read 
>> user-data and tell Chef on the node what its role is (amongst other 
>> things). It's a kludge. I'm going to be looking into integrating Chef with 
>> CloudFormation, which plays nice(r) with ASGs.
>>
>> http://aws.amazon.com/cloudformation/aws-cloudformation-articles-and-tutorials/
>>  (second link)
>> https://s3.amazonaws.com/cloudformation-examples/IntegratingAWSCloudFormationWithOpscodeChef.pdf
>>
>> -john
>>
>> On Nov 10, 2011, at 9:44 AM, 
>> <
 >
>>  
>> <
 >
>>  wrote:
>>
>>> Hi all, I'd like to get some feedback on how people are doing this now. It
>>> seems that since .10, the preferred way of starting Amazon EC2 instances 
>>> is via
>>> the 'knife ec2 server create' command, while the 'knife ec2 instance 
>>> data' and
>>> chef preinstalled AMIs are deprecated. That's all fine and good for 
>>> manually
>>> launching instances, but what about autoscaling? When a node comes up for
>>> autoscalling, I want it to update and configure itself according to its 
>>> role(s)
>>> and environment. With the instance data method of doing thing deprecated,
>>> what's the alternative (aside from having a custom baked AMI that I need 
>>> to
>>> manually update as is the normal way of doing this without chef)? If 
>>> there is
>>> no alternative, and I have to use the deprecated method which would mean 
>>> using
>>> 'knife ec2 instance data' to wire into the autoscaling group as UserData. 
>>> When
>>> using this method how would I specify the environment that the server 
>>> should be
>>> run as too? I don't see anyway to do this using the instance data. 
>>> Running some
>>> command outside the server after the server it is started to set the
>>> environment is not an option as we won't know when a new server has been 
>>> spun
>>> up (controlled by Amazon).
>>>
>>> I'm interested in what other people have found to be best practice for 
>>> this
>>> scenario and any advice, tips or tricks that have been learned while 
>>> trying to
>>> work with chef and autoscaled EC2 instances.
>>>
>>> Thanks for your thoughts!
>>
>
>