[chef] Re: Re: Re: using env attr to override a default

[AJ Christensen < >]

Yo,

Thanks for the paste, comments in-line:

On 28 September 2011 07:32,  
<
 >
 wrote:
> On Tue, 27 Sep 2011, AJ Christensen wrote:
>
>> Yo,
>>
>> Your environments attributes are wrong:
>>
>> On 27 September 2011 17:49,  
>> <
 >
>>  wrote:
>> >
>> > first, the prod and dev environments:
>> >
>> >    [chef-repo]$ knife environment show dev
>> >    chef_type:            environment
>> >    cookbook_versions:
>> >    default_attributes:
>> >      mail-client:
>> >        relayhost:  mungbeans.dev.dorqtown.com
>> >      mail-server:
>> >        relayhost:  [smtp.gmail.com]:587
>> >    description:          Development environment (dev)
>> >    json_class:           Chef::Environment
>> >    name:                 dev
>> >    override_attributes:


>>
>> this should be:
>> default_attributes "postfix" => { "relayhost" => "whatever" }
>>
>> The attributes are deep merged together onto the node and thus the
>> atribute structure must remain the same. Does this make sense?
>>
>> If you can post the on-disk, ruby version of the environment files I
>> can point out the problem, otherwise good luck!
>
> i can show you the json version of the env files. i was trying to
> cobble together the ruby, but not getting it quickly. for the sake of
> speed i'll show the json. i see what you're saying about attribute
> structure, so i corrected it, i believe. but the client's relayhost
> in main.cf is still picking up the setting from the postfix cookbook
> attr setting rather than the dev env setting.
>
> [chef-repo]$ cat environments/dev.json
> {
>  "name": "dev",
>  "default_attributes": {
>    "postfix": {
>      "mail-server": {
>        "relayhost": "[outbound.mailhop.org],[smtp.gmail.com]:587"
>      },
>      "mail-client": {
>        "relayhost": "mungbeans.dev.dorqtown.com"
>      }
>    }
>  },
>  "json_class": "Chef::Environment",
>  "description": "Development environment (dev)",
>  "chef_type": "environment"
> }

This new one is bad too. The structure you want, quote unquote, is:

"default_attributes": {
  "postfix": { "relayhost" : "mungbeans.dev.dorqtown.com" }
}

Notice the wildly obvious exclusion of any mention of the "name" of
your other roles, "mail-server" and "mail-client" - the names of the
roles are irrelevant. they are *attribute holders* - you will unlikely
ever refer to them by name apart from when doing a Search or run_list
introspection for dual-behavior.

This whole pattern you're in - setting things globally - is a sure
sign of a cfengine "expert". In chef, you do *not* want to be doing
that configuration - you want to be discovering it. The relay server
node can expose attributes to the search index, which is exposed to
all nodes with access. You can simply query for a combination of a
recipe + particular attribute/value.

I'd suggest using the existing Opscode cookbooks which already
implement Search for discovery of the local relay master, by toggling
an attribute.

https://github.com/opscode/cookbooks/blob/master/postfix/attributes/default.rb#L1

e.g.

role postfix_client defaults postfix.client_type = "client"
role postfix_server defaults postfix.client_type = "master"

Done.

–AJ

>
> [chef-repo]$ knife node show sous-chef1.dev.dorqtown.com -r
> run_list:  role[mail-client]
>
> [sous-chef1-dev ~]# grep relayhost /etc/postfix/main.cf
> relayhost = mailrelay.dev.dorqtown.com
>
>
> where to look?
>
>