[chef] Re: Re: Re: Re: Re: Re: Re: AWS cookbook and the run list

["Julian C. Dunn" < >]

I think you're down a rabbit-hole of circular preconditions here.

The purpose of the aws::ec2_hints recipe is to create the hints file
when you, the operator, are sure that the box is running on EC2. You
can't just unconditionally run that recipe because it would just cause
the rest of the Chef run to assume you're always running under EC2.

Using another attribute (node['cloud']['provider'] or whatnot) won't
really help, because the point is that there's no reliable way to
automatically detect if a box is in EC2 or not. Hence the need for the
hints file.

A couple points of advice:

1. You may or may not even need the hints file if Ohai can actually
detect that your box is in EC2.
2. If that doesn't work, drop the file off during the initial
bootstrap, outside of a recipe. knife-ec2 will do this for you.
3. Alternately, use some other condition that you trust to determine
whether the box is in EC2, and set the hint and/or invoke
aws::ec2_hints appropriately. e.g.

if some_connection_to_the_ec2_metadata_service_worked
  include_recipe('aws::ec2_hints')
end

4. env_run_lists are, more often than not, an unnecessary complication
and I'd avoid them where possible.

- Julian

On Mon, Jan 26, 2015 at 8:47 PM, Greg Barker 
<
 >
 wrote:
> I was hoping to avoid adding complexity to the run list by creating a new
> environment for EC2 and having to specify the env_run_lists in my base role.
> If I'm going down that route I would probably just put
> mycookbook::ec2_specific_
> thing on the run_list there, which negates the necessity for using if
> node["ec2"].
>
> It seems like a much simpler way to solve it would be something like:
>
> if !node["ec2"].empty?
>   include_recipe "mycookbook::ec2_specific_thing"
> end
>
> Or maybe relying on another attribute like node['cloud']['provider']?
>
> Or am I crazy for trying to avoid env_run_lists here?
>
> Greg
>
> On Sat, Jan 24, 2015 at 9:46 AM, Julian C. Dunn 
> <
 >
>  wrote:
>>
>> Ah yes. I missed the first part of Greg's email that stated that his
>> run_list contains recipe[aws::ec2_hints]. So... maybe not a good thing
>> to do when running under Vagrant :-)
>>
>> - Julian
>>
>> On Fri, Jan 23, 2015 at 7:29 PM, Daniel Condomitti
>> <
 >
>>  wrote:
>> > Julian,
>> >
>> > That’s the expected behavior, right? aws::ec2_hints adds the ec2 hints
>> > file
>> > for ohai which causes the node to be recognized as EC2 even if it isn’t.
>> > It
>> > doesn’t have any normal attributes populated but the node[‘ec2’] key
>> > exists.
>> >
>> > This is a CentOS 6.5 node running in VirtualBox
>> >
>> > # chef-shell -z
>> > ...
>> > chef > File.exists?('/etc/chef/ohai/hints/ec2.json')
>> >  => false
>> > chef > node['ec2']
>> >  => nil
>> > chef > exit
>> >
>> > # mkdir -p /etc/chef/ohai/hints
>> > # touch ohai/hints/ec2.json
>> > # chef-shell -z
>> >
>> > ....
>> > chef > File.exists?('/etc/chef/ohai/hints/ec2.json')
>> >  => true
>> > chef > node['ec2']
>> >  => #<Chef::Node::Attribute @normal={...}, @current_normal=nil,
>> > @default={...}, @current_default=nil, @override={...},
>> > @current_override=nil, @automatic={...}, @current_automatic={},
>> > @current_nesting_level=["ec2"], @auto_vivifiy_on_read=false,
>> > @set_unless_value_present=false, @set_type=nil, @has_been_read=false>
>> >
>> >
>> > On Friday, January 23, 2015 at 7:11 PM, Julian C. Dunn wrote:
>> >
>> > On Wed, Jan 21, 2015 at 10:07 PM, Greg Barker 
>> > <
 >
>> > wrote:
>> >
>> > So I added this to my metadata.rb:
>> >
>> > depends 'aws'
>> >
>> > Added this to my run_list:
>> >
>> > "recipe[aws]",
>> > "recipe[aws::ec2_hints]",
>> >
>> > Added this to my recipe:
>> >
>> > if node["ec2"]
>> > include_recipe "mycookbook::ec2_specific_thing"
>> > end
>> >
>> > Works great when I ran it on an EC2 instance. But when I tried a
>> > `vagrant
>> > up` for a local VM, it hits an error in my ec2_specific_thing recipe. I
>> > thought it wasn't going to be executed at all though. Any ideas?
>> >
>> >
>> > That shouldn't happen. Can you paste the error?
>> >
>> > - Julian
>> >
>> >
>>
>>
>>
>> --
>> [ Julian C. Dunn 
>> <
 >
>>           * Sorry, I'm    ]
>> [ WWW: http://www.aquezada.com/staff/julian    * only Web 1.0  ;]
>> [ gopher://sdf.org/1/users/keymaker/           * compliant!    ;]
>> [ PGP: 91B3 7A9D 683C 7C16 715F 442C 6065 D533 FDC2 05B9       ]
>
>



-- 
[ Julian C. Dunn 
<
 >
          * Sorry, I'm    ]
[ WWW: http://www.aquezada.com/staff/julian    * only Web 1.0  ;]
[ gopher://sdf.org/1/users/keymaker/           * compliant!    ;]
[ PGP: 91B3 7A9D 683C 7C16 715F 442C 6065 D533 FDC2 05B9       ]