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Zachary Stern

2012-Aug-12 00:45 UTC

[Puppet Users] variable scoping?

I''m having a really hard time grasping how variables are scoped in
puppet (not really much of a programmer).

I''ve got a manifest that looks like this:
###
class puppet::config {
  include puppet::params
  file { ''/etc/puppet/puppet.conf'':
    ensure  => present,
    content => template(''puppet/puppet.conf.erb''),
    owner   => ''root'',
    group   => ''admins'',
    require => Class[''puppet::install''],
    notify  => Class[''puppet::service''],
    }
}
###


I''ve then got a manifest like this, which has a class being included
above:
###
class puppet::params {
  $puppetserver = ''command.enterawesome.com''
}
###

The template being used in the first class includes the variable
$puppetserver, but somehow, the include statement isn''t enough for the
variable to be defined within the scope of the manifest/template
above.
What gives?
It works just fine if I include a statement like this in the erb file:
<%= scope.lookupvar(''puppet::params::puppetserver'') %>

But I''d really like to understand scoping better. What is it I need to
do to just refer to the variable by name? Why isn''t the include
statement enough? Isn''t in including the puppet::params class inside
the puppet::config class, and therefore having the variable defined in
that context? Apparently not. But I don''t understand why. I
wan''t to
end up at a point where the variable is in the proper scope, such that
I can just have a statement like <%= puppetserver %> inside of the
template I''m using.

Thanks in advance!

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Eric Shamow

2012-Aug-12 02:36 UTC

head link

Re: [Puppet Users] variable scoping?

The best reference to explain how variable scoping works in Puppet is this one -

http://docs.puppetlabs.com/guides/scope_and_puppet.html

Scoping has changed with 2.7, so you may find some confusing references online
that follow the pre-2.7 rules. In general the 2.7 changes are designed to
introduce some sanity to variable scopes and eliminate dynamic scoping, which
causes all kinds of pain.

The easiest way to think about scoping in general is that a scope is defined by
its container. If I put something physical in a box, I have access to it the
moment I open the box, and other objects inside the box can interact with it.
If, however, I now put that box inside a second box, the objects in the second
box cannot interact directly with the objects in the first - the first object is
protected by its container.

Scoping mostly works the same way. The right way to get at the variable is to
always explicitly scope, as you began to get at below with your scope.lookupvar
example. As that can be a bit of a pain to repeat, you can always copy the value
into a local variable:

class puppet::config {
include puppet::params
$puppetserver = puppet::params::puppetserver
…
}

-Eric  

--  

Eric Shamow
Professional Services
http://puppetlabs.com/
©631.871.6441

Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
Francisco, California on September 27th and 28th --> http://bit.ly/pcsig12


On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote:
> I''m having a really hard time grasping how variables are scoped in
> puppet (not really much of a programmer).
>  
> I''ve got a manifest that looks like this:
> ###
> class puppet::config {
> include puppet::params
> file { ''/etc/puppet/puppet.conf'':
> ensure => present,
> content => template(''puppet/puppet.conf.erb''),
> owner => ''root'',
> group => ''admins'',
> require => Class[''puppet::install''],
> notify => Class[''puppet::service''],
> }
> }
> ###
>  
>  
> I''ve then got a manifest like this, which has a class being
included above:
> ###
> class puppet::params {
> $puppetserver = ''command.enterawesome.com
(http://command.enterawesome.com)''
> }
> ###
>  
> The template being used in the first class includes the variable
> $puppetserver, but somehow, the include statement isn''t enough for
the
> variable to be defined within the scope of the manifest/template
> above.
> What gives?
> It works just fine if I include a statement like this in the erb file:
> <%= scope.lookupvar(''puppet::params::puppetserver'')
%>
>  
> But I''d really like to understand scoping better. What is it I
need to
> do to just refer to the variable by name? Why isn''t the include
> statement enough? Isn''t in including the puppet::params class
inside
> the puppet::config class, and therefore having the variable defined in
> that context? Apparently not. But I don''t understand why. I
wan''t to
> end up at a point where the variable is in the proper scope, such that
> I can just have a statement like <%= puppetserver %> inside of the
> template I''m using.
>  
> Thanks in advance!
>  
> --  
> You received this message because you are subscribed to the Google Groups
"Puppet Users" group.
> To post to this group, send email to puppet-users@googlegroups.com
(mailto:puppet-users@googlegroups.com).
> To unsubscribe from this group, send email to
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(mailto:puppet-users+unsubscribe@googlegroups.com).
> For more options, visit this group at
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Eric Shamow

2012-Aug-12 02:37 UTC

head link

Re: [Puppet Users] variable scoping?

Sorry, that should be

$puppetserver = $puppet::params::puppetserver

-Eric  

--  

Eric Shamow
Professional Services
http://puppetlabs.com/
©631.871.6441

Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
Francisco, California on September 27th and 28th --> http://bit.ly/pcsig12


On Saturday, August 11, 2012 at 10:36 PM, Eric Shamow wrote:
> The best reference to explain how variable scoping works in Puppet is this
one -
>  
> http://docs.puppetlabs.com/guides/scope_and_puppet.html
>  
> Scoping has changed with 2.7, so you may find some confusing references
online that follow the pre-2.7 rules. In general the 2.7 changes are designed to
introduce some sanity to variable scopes and eliminate dynamic scoping, which
causes all kinds of pain.
>  
> The easiest way to think about scoping in general is that a scope is
defined by its container. If I put something physical in a box, I have access to
it the moment I open the box, and other objects inside the box can interact with
it. If, however, I now put that box inside a second box, the objects in the
second box cannot interact directly with the objects in the first - the first
object is protected by its container.
>  
> Scoping mostly works the same way. The right way to get at the variable is
to always explicitly scope, as you began to get at below with your
scope.lookupvar example. As that can be a bit of a pain to repeat, you can
always copy the value into a local variable:
>  
> class puppet::config {
> include puppet::params
> $puppetserver = puppet::params::puppetserver
> …
> }
>  
> -Eric  
>  
> --  
>  
> Eric Shamow
> Professional Services
> http://puppetlabs.com/
> ©631.871.6441
>  
> Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
Francisco, California on September 27th and 28th --> http://bit.ly/pcsig12
>  
>  
> On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote:
>  
> > I''m having a really hard time grasping how variables are
scoped in
> > puppet (not really much of a programmer).
> >  
> > I''ve got a manifest that looks like this:
> > ###
> > class puppet::config {
> > include puppet::params
> > file { ''/etc/puppet/puppet.conf'':
> > ensure => present,
> > content => template(''puppet/puppet.conf.erb''),
> > owner => ''root'',
> > group => ''admins'',
> > require => Class[''puppet::install''],
> > notify => Class[''puppet::service''],
> > }
> > }
> > ###
> >  
> >  
> > I''ve then got a manifest like this, which has a class being
included above:
> > ###
> > class puppet::params {
> > $puppetserver = ''command.enterawesome.com
(http://command.enterawesome.com)''
> > }
> > ###
> >  
> > The template being used in the first class includes the variable
> > $puppetserver, but somehow, the include statement isn''t
enough for the
> > variable to be defined within the scope of the manifest/template
> > above.
> > What gives?
> > It works just fine if I include a statement like this in the erb file:
> > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
> >  
> > But I''d really like to understand scoping better. What is it
I need to
> > do to just refer to the variable by name? Why isn''t the
include
> > statement enough? Isn''t in including the puppet::params class
inside
> > the puppet::config class, and therefore having the variable defined in
> > that context? Apparently not. But I don''t understand why. I
wan''t to
> > end up at a point where the variable is in the proper scope, such that
> > I can just have a statement like <%= puppetserver %> inside of
the
> > template I''m using.
> >  
> > Thanks in advance!
> >  
> > --  
> > You received this message because you are subscribed to the Google
Groups "Puppet Users" group.
> > To post to this group, send email to puppet-users@googlegroups.com
(mailto:puppet-users@googlegroups.com).
> > To unsubscribe from this group, send email to
puppet-users+unsubscribe@googlegroups.com
(mailto:puppet-users+unsubscribe@googlegroups.com).
> > For more options, visit this group at
http://groups.google.com/group/puppet-users?hl=en.
>  


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Zachary Alex Stern

2012-Aug-12 03:23 UTC

head link

Re: [Puppet Users] variable scoping?

>
> Sorry, that should be 
>
> $puppetserver = $puppet::params::puppetserver 
>
> -Eric   
>
>Seems like at that point I may as well just do this inside the template: 
<%= scope.lookupvar(''puppet::params::puppetserver'') %> 

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Zachary Alex Stern

2012-Aug-12 05:24 UTC

head link

Re: [Puppet Users] variable scoping?

Also, fwiw, I''ve read that document on scoping beginning to end several
times. Doesn''t mean much to me I''m afraid - pretty new to all
this.

On Saturday, August 11, 2012 10:36:48 PM UTC-4, Eric Shamow
wrote:>
> The best reference to explain how variable scoping works in Puppet is this 
> one - 
>
> http://docs.puppetlabs.com/guides/scope_and_puppet.html 
>
> Scoping has changed with 2.7, so you may find some confusing references 
> online that follow the pre-2.7 rules. In general the 2.7 changes are 
> designed to introduce some sanity to variable scopes and eliminate dynamic 
> scoping, which causes all kinds of pain. 
>
> The easiest way to think about scoping in general is that a scope is 
> defined by its container. If I put something physical in a box, I have 
> access to it the moment I open the box, and other objects inside the box 
> can interact with it. If, however, I now put that box inside a second box, 
> the objects in the second box cannot interact directly with the objects in 
> the first - the first object is protected by its container. 
>
> Scoping mostly works the same way. The right way to get at the variable is 
> to always explicitly scope, as you began to get at below with your 
> scope.lookupvar example. As that can be a bit of a pain to repeat, you can 
> always copy the value into a local variable: 
>
> class puppet::config { 
> include puppet::params 
> $puppetserver = puppet::params::puppetserver 
> … 
> } 
>
> -Eric   
>
> --   
>
> Eric Shamow 
> Professional Services 
> http://puppetlabs.com/ 
> ©631.871.6441 
>
> Join us for PuppetConf 2012 at the Mission Bay Convention Center in San 
> Francisco, California on September 27th and 28th -->
http://bit.ly/pcsig12
>
>
> On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote: 
>
> > I''m having a really hard time grasping how variables are
scoped in
> > puppet (not really much of a programmer). 
> >   
> > I''ve got a manifest that looks like this: 
> > ### 
> > class puppet::config { 
> > include puppet::params 
> > file { ''/etc/puppet/puppet.conf'': 
> > ensure => present, 
> > content => template(''puppet/puppet.conf.erb''), 
> > owner => ''root'', 
> > group => ''admins'', 
> > require => Class[''puppet::install''], 
> > notify => Class[''puppet::service''], 
> > } 
> > } 
> > ### 
> >   
> >   
> > I''ve then got a manifest like this, which has a class being
included
> above: 
> > ### 
> > class puppet::params { 
> > $puppetserver = ''command.enterawesome.com (
> http://command.enterawesome.com)'' 
> > } 
> > ### 
> >   
> > The template being used in the first class includes the variable 
> > $puppetserver, but somehow, the include statement isn''t
enough for the
> > variable to be defined within the scope of the manifest/template 
> > above. 
> > What gives? 
> > It works just fine if I include a statement like this in the erb file:
> > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
> >   
> > But I''d really like to understand scoping better. What is it
I need to
> > do to just refer to the variable by name? Why isn''t the
include
> > statement enough? Isn''t in including the puppet::params class
inside
> > the puppet::config class, and therefore having the variable defined in
> > that context? Apparently not. But I don''t understand why. I
wan''t to
> > end up at a point where the variable is in the proper scope, such that
> > I can just have a statement like <%= puppetserver %> inside of
the
> > template I''m using. 
> >   
> > Thanks in advance! 
> >   
> > --   
> > You received this message because you are subscribed to the Google 
> Groups "Puppet Users" group. 
> > To post to this group, send email to
puppet...@googlegroups.com<javascript:>(mailto:
> puppet...@googlegroups.com <javascript:>). 
> > To unsubscribe from this group, send email to 
> puppet-users...@googlegroups.com <javascript:> (mailto:
> puppet-users+unsubscribe@googlegroups.com <javascript:>). 
> > For more options, visit this group at 
> http://groups.google.com/group/puppet-users?hl=en. 
>
>
>
>
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Douglas Garstang

2012-Aug-12 05:33 UTC

head link

Re: [Puppet Users] variable scoping?

I feel your pain.

On Sat, Aug 11, 2012 at 10:24 PM, Zachary Alex Stern
<zs@enternewmedia.com> wrote:> Also, fwiw, I''ve read that document on scoping beginning to end
several
> times. Doesn''t mean much to me I''m afraid - pretty new to
all this.
>
>
> On Saturday, August 11, 2012 10:36:48 PM UTC-4, Eric Shamow wrote:
>>
>> The best reference to explain how variable scoping works in Puppet is
this
>> one -
>>
>> http://docs.puppetlabs.com/guides/scope_and_puppet.html
>>
>> Scoping has changed with 2.7, so you may find some confusing references
>> online that follow the pre-2.7 rules. In general the 2.7 changes are
>> designed to introduce some sanity to variable scopes and eliminate
dynamic
>> scoping, which causes all kinds of pain.
>>
>> The easiest way to think about scoping in general is that a scope is
>> defined by its container. If I put something physical in a box, I have
>> access to it the moment I open the box, and other objects inside the
box can
>> interact with it. If, however, I now put that box inside a second box,
the
>> objects in the second box cannot interact directly with the objects in
the
>> first - the first object is protected by its container.
>>
>> Scoping mostly works the same way. The right way to get at the variable
is
>> to always explicitly scope, as you began to get at below with your
>> scope.lookupvar example. As that can be a bit of a pain to repeat, you
can
>> always copy the value into a local variable:
>>
>> class puppet::config {
>> include puppet::params
>> $puppetserver = puppet::params::puppetserver
>> …
>> }
>>
>> -Eric
>>
>> --
>>
>> Eric Shamow
>> Professional Services
>> http://puppetlabs.com/
>> ©631.871.6441
>>
>> Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
>> Francisco, California on September 27th and 28th -->
http://bit.ly/pcsig12
>>
>>
>> On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote:
>>
>> > I''m having a really hard time grasping how variables are
scoped in
>> > puppet (not really much of a programmer).
>> >
>> > I''ve got a manifest that looks like this:
>> > ###
>> > class puppet::config {
>> > include puppet::params
>> > file { ''/etc/puppet/puppet.conf'':
>> > ensure => present,
>> > content =>
template(''puppet/puppet.conf.erb''),
>> > owner => ''root'',
>> > group => ''admins'',
>> > require => Class[''puppet::install''],
>> > notify => Class[''puppet::service''],
>> > }
>> > }
>> > ###
>> >
>> >
>> > I''ve then got a manifest like this, which has a class
being included
>> > above:
>> > ###
>> > class puppet::params {
>> > $puppetserver = ''command.enterawesome.com
>> > (http://command.enterawesome.com)''
>> > }
>> > ###
>> >
>> > The template being used in the first class includes the variable
>> > $puppetserver, but somehow, the include statement isn''t
enough for the
>> > variable to be defined within the scope of the manifest/template
>> > above.
>> > What gives?
>> > It works just fine if I include a statement like this in the erb
file:
>> > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
>> >
>> > But I''d really like to understand scoping better. What is
it I need to
>> > do to just refer to the variable by name? Why isn''t the
include
>> > statement enough? Isn''t in including the puppet::params
class inside
>> > the puppet::config class, and therefore having the variable
defined in
>> > that context? Apparently not. But I don''t understand why.
I wan''t to
>> > end up at a point where the variable is in the proper scope, such
that
>> > I can just have a statement like <%= puppetserver %> inside
of the
>> > template I''m using.
>> >
>> > Thanks in advance!
>> >
>> > --
>> > You received this message because you are subscribed to the Google
>> > Groups "Puppet Users" group.
>> > To post to this group, send email to puppet...@googlegroups.com
>> > (mailto:puppet...@googlegroups.com).
>> > To unsubscribe from this group, send email to
>> > puppet-users...@googlegroups.com
>> > (mailto:puppet-users+unsubscribe@googlegroups.com).
>> > For more options, visit this group at
>> > http://groups.google.com/group/puppet-users?hl=en.
>>
>>
>>
> --
> You received this message because you are subscribed to the Google Groups
> "Puppet Users" group.
> To view this discussion on the web visit
> https://groups.google.com/d/msg/puppet-users/-/IgWXSc13m04J.
>
> To post to this group, send email to puppet-users@googlegroups.com.
> To unsubscribe from this group, send email to
> puppet-users+unsubscribe@googlegroups.com.
> For more options, visit this group at
> http://groups.google.com/group/puppet-users?hl=en.


-- 
Regards,

Douglas Garstang
http://www.linkedin.com/in/garstang
Email: doug.garstang@gmail.com
Cell: +1-805-340-5627

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Eric Shamow

2012-Aug-12 05:38 UTC

head link

Re: [Puppet Users] variable scoping?

Zachary,

Is there a particular section of the scoping doc I can help you understand?

-Eric  

--  

Eric Shamow
Professional Services
http://puppetlabs.com/
©631.871.6441

Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
Francisco, California on September 27th and 28th --> http://bit.ly/pcsig12


On Sunday, August 12, 2012 at 1:24 AM, Zachary Alex Stern wrote:
> Also, fwiw, I''ve read that document on scoping beginning to end
several times. Doesn''t mean much to me I''m afraid - pretty new
to all this.
>  
> On Saturday, August 11, 2012 10:36:48 PM UTC-4, Eric Shamow wrote:
> > The best reference to explain how variable scoping works in Puppet is
this one -
> >  
> > http://docs.puppetlabs.com/guides/scope_and_puppet.html  
> >  
> > Scoping has changed with 2.7, so you may find some confusing
references online that follow the pre-2.7 rules. In general the 2.7 changes are
designed to introduce some sanity to variable scopes and eliminate dynamic
scoping, which causes all kinds of pain.
> >  
> > The easiest way to think about scoping in general is that a scope is
defined by its container. If I put something physical in a box, I have access to
it the moment I open the box, and other objects inside the box can interact with
it. If, however, I now put that box inside a second box, the objects in the
second box cannot interact directly with the objects in the first - the first
object is protected by its container.
> >  
> > Scoping mostly works the same way. The right way to get at the
variable is to always explicitly scope, as you began to get at below with your
scope.lookupvar example. As that can be a bit of a pain to repeat, you can
always copy the value into a local variable:
> >  
> > class puppet::config {  
> > include puppet::params  
> > $puppetserver = puppet::params::puppetserver  
> > …  
> > }  
> >  
> > -Eric  
> >  
> > --  
> >  
> > Eric Shamow  
> > Professional Services  
> > http://puppetlabs.com/  
> > ©631.871.6441  
> >  
> > Join us for PuppetConf 2012 at the Mission Bay Convention Center in
San Francisco, California on September 27th and 28th -->
http://bit.ly/pcsig12
> >  
> >  
> > On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote:  
> >  
> > > I''m having a really hard time grasping how variables are
scoped in
> > > puppet (not really much of a programmer).  
> > >  
> > > I''ve got a manifest that looks like this:  
> > > ###  
> > > class puppet::config {  
> > > include puppet::params  
> > > file { ''/etc/puppet/puppet.conf'':  
> > > ensure => present,  
> > > content =>
template(''puppet/puppet.conf.erb''),
> > > owner => ''root'',  
> > > group => ''admins'',  
> > > require => Class[''puppet::install''],  
> > > notify => Class[''puppet::service''],  
> > > }  
> > > }  
> > > ###  
> > >  
> > >  
> > > I''ve then got a manifest like this, which has a class
being included above:
> > > ###  
> > > class puppet::params {  
> > > $puppetserver = ''command.enterawesome.com
(http://command.enterawesome.com) (http://command.enterawesome.com)''
> > > }  
> > > ###  
> > >  
> > > The template being used in the first class includes the variable
> > > $puppetserver, but somehow, the include statement isn''t
enough for the
> > > variable to be defined within the scope of the manifest/template
> > > above.  
> > > What gives?  
> > > It works just fine if I include a statement like this in the erb
file:
> > > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
> > >  
> > > But I''d really like to understand scoping better. What
is it I need to
> > > do to just refer to the variable by name? Why isn''t the
include
> > > statement enough? Isn''t in including the puppet::params
class inside
> > > the puppet::config class, and therefore having the variable
defined in
> > > that context? Apparently not. But I don''t understand
why. I wan''t to
> > > end up at a point where the variable is in the proper scope, such
that
> > > I can just have a statement like <%= puppetserver %> inside
of the
> > > template I''m using.  
> > >  
> > > Thanks in advance!  
> > >  
> > > --  
> > > You received this message because you are subscribed to the
Google Groups "Puppet Users" group.
> > > To post to this group, send email to puppet...@googlegroups.com
(javascript:) (mailto:puppet...@googlegroups.com (javascript:)).
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(mailto:puppet-users+unsubscribe@googlegroups.com (javascript:)).
> > > For more options, visit this group at
http://groups.google.com/group/puppet-users?hl=en.
> >  
>  
> --  
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Zachary Alex Stern

2012-Aug-12 06:35 UTC

head link

Re: [Puppet Users] variable scoping?

So, your explanation makes sense to me - but that doesn''t exactly
explain
to me why the "include" statement isn''t enough.

E.g. when I''m "including the puppet::params class in the
puppet::config
class, what affect is it having at all, if not setting things like the 
variables included in the original puppet::params class?

How can I change variables on the fly effectively, if I can''t just do
the
import and then have the variable $puppetserver equal the one from the 
imported class? I''m having a hard time grasping what import does, if
not
this.

On Saturday, August 11, 2012 10:36:48 PM UTC-4, Eric Shamow
wrote:>
> The best reference to explain how variable scoping works in Puppet is this 
> one - 
>
> http://docs.puppetlabs.com/guides/scope_and_puppet.html 
>
> Scoping has changed with 2.7, so you may find some confusing references 
> online that follow the pre-2.7 rules. In general the 2.7 changes are 
> designed to introduce some sanity to variable scopes and eliminate dynamic 
> scoping, which causes all kinds of pain. 
>
> The easiest way to think about scoping in general is that a scope is 
> defined by its container. If I put something physical in a box, I have 
> access to it the moment I open the box, and other objects inside the box 
> can interact with it. If, however, I now put that box inside a second box, 
> the objects in the second box cannot interact directly with the objects in 
> the first - the first object is protected by its container. 
>
> Scoping mostly works the same way. The right way to get at the variable is 
> to always explicitly scope, as you began to get at below with your 
> scope.lookupvar example. As that can be a bit of a pain to repeat, you can 
> always copy the value into a local variable: 
>
> class puppet::config { 
> include puppet::params 
> $puppetserver = puppet::params::puppetserver 
> … 
> } 
>
> -Eric   
>
> --   
>
> Eric Shamow 
> Professional Services 
> http://puppetlabs.com/ 
> ©631.871.6441 
>
> Join us for PuppetConf 2012 at the Mission Bay Convention Center in San 
> Francisco, California on September 27th and 28th -->
http://bit.ly/pcsig12
>
>
> On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote: 
>
> > I''m having a really hard time grasping how variables are
scoped in
> > puppet (not really much of a programmer). 
> >   
> > I''ve got a manifest that looks like this: 
> > ### 
> > class puppet::config { 
> > include puppet::params 
> > file { ''/etc/puppet/puppet.conf'': 
> > ensure => present, 
> > content => template(''puppet/puppet.conf.erb''), 
> > owner => ''root'', 
> > group => ''admins'', 
> > require => Class[''puppet::install''], 
> > notify => Class[''puppet::service''], 
> > } 
> > } 
> > ### 
> >   
> >   
> > I''ve then got a manifest like this, which has a class being
included
> above: 
> > ### 
> > class puppet::params { 
> > $puppetserver = ''command.enterawesome.com (
> http://command.enterawesome.com)'' 
> > } 
> > ### 
> >   
> > The template being used in the first class includes the variable 
> > $puppetserver, but somehow, the include statement isn''t
enough for the
> > variable to be defined within the scope of the manifest/template 
> > above. 
> > What gives? 
> > It works just fine if I include a statement like this in the erb file:
> > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
> >   
> > But I''d really like to understand scoping better. What is it
I need to
> > do to just refer to the variable by name? Why isn''t the
include
> > statement enough? Isn''t in including the puppet::params class
inside
> > the puppet::config class, and therefore having the variable defined in
> > that context? Apparently not. But I don''t understand why. I
wan''t to
> > end up at a point where the variable is in the proper scope, such that
> > I can just have a statement like <%= puppetserver %> inside of
the
> > template I''m using. 
> >   
> > Thanks in advance! 
> >   
> > --   
> > You received this message because you are subscribed to the Google 
> Groups "Puppet Users" group. 
> > To post to this group, send email to
puppet...@googlegroups.com<javascript:>(mailto:
> puppet...@googlegroups.com <javascript:>). 
> > To unsubscribe from this group, send email to 
> puppet-users...@googlegroups.com <javascript:> (mailto:
> puppet-users+unsubscribe@googlegroups.com <javascript:>). 
> > For more options, visit this group at 
> http://groups.google.com/group/puppet-users?hl=en. 
>
>
>
>
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Eric Shamow

2012-Aug-12 12:43 UTC

head link

Re: [Puppet Users] variable scoping?

First off, it''s important to distinguish import from include. They
"feel" like similar concepts but they''re not - import goes
and physically loads a file. Include says "ensure that this class is part
of this host''s resource graph."

It''s important not to think of Puppet in procedural, top-down terms. We
haven''t just said, "give me all the stuff in this class, and now
do these things." Rather we are building a model of a server, and manifest
code simply informs pieces of that model. So by saying "include
<class>" you are really saying, "Puppet, if you haven''t
already, make sure this class is part of the overall resource graph."

The better model for this example is, rather than a box inside of a box, you are
looking at two sealed boxes sitting side by side. When you include the first
group, it is added to the list of boxes used. Within the first box, when you
then say "give me the second box," that second box is placed
*alongside* the first. Thus in order to grab anything from it, you have to
specify "I need the stuff from box 2."

Does that analogy help a bit more?

The reason for this is that, as your number of classes grows, so too will your
variables. If they share a single global namespace, the likelihood of a global
variable name being used more than once increases. This can lead to really
unexpected changes and ambiguity in building the graph.

An example: suppose is this module you say $puppetmaster =
"myserver.local" and in another module, you want to only run on a
puppet master and so say $puppetmaster = true. When Puppet assembles the model
of your system, which of the two is to be applied where? Dynamic scoping tried
to guess at this. The idea here is to say, eliminate ambiguity - tell us exactly
which one you want.

-Eric  

--  

Eric Shamow
Professional Services
http://puppetlabs.com/
©631.871.6441

Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
Francisco, California on September 27th and 28th --> http://bit.ly/pcsig12


On Sunday, August 12, 2012 at 2:35 AM, Zachary Alex Stern wrote:
> So, your explanation makes sense to me - but that doesn''t exactly
explain to me why the "include" statement isn''t enough.
>  
> E.g. when I''m "including the puppet::params class in the
puppet::config class, what affect is it having at all, if not setting things
like the variables included in the original puppet::params class?
>  
> How can I change variables on the fly effectively, if I can''t just
do the import and then have the variable $puppetserver equal the one from the
imported class? I''m having a hard time grasping what import does, if
not this.
>  
> On Saturday, August 11, 2012 10:36:48 PM UTC-4, Eric Shamow wrote:
> > The best reference to explain how variable scoping works in Puppet is
this one -
> >  
> > http://docs.puppetlabs.com/guides/scope_and_puppet.html  
> >  
> > Scoping has changed with 2.7, so you may find some confusing
references online that follow the pre-2.7 rules. In general the 2.7 changes are
designed to introduce some sanity to variable scopes and eliminate dynamic
scoping, which causes all kinds of pain.
> >  
> > The easiest way to think about scoping in general is that a scope is
defined by its container. If I put something physical in a box, I have access to
it the moment I open the box, and other objects inside the box can interact with
it. If, however, I now put that box inside a second box, the objects in the
second box cannot interact directly with the objects in the first - the first
object is protected by its container.
> >  
> > Scoping mostly works the same way. The right way to get at the
variable is to always explicitly scope, as you began to get at below with your
scope.lookupvar example. As that can be a bit of a pain to repeat, you can
always copy the value into a local variable:
> >  
> > class puppet::config {  
> > include puppet::params  
> > $puppetserver = puppet::params::puppetserver  
> > …  
> > }  
> >  
> > -Eric  
> >  
> > --  
> >  
> > Eric Shamow  
> > Professional Services  
> > http://puppetlabs.com/  
> > ©631.871.6441  
> >  
> > Join us for PuppetConf 2012 at the Mission Bay Convention Center in
San Francisco, California on September 27th and 28th -->
http://bit.ly/pcsig12
> >  
> >  
> > On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote:  
> >  
> > > I''m having a really hard time grasping how variables are
scoped in
> > > puppet (not really much of a programmer).  
> > >  
> > > I''ve got a manifest that looks like this:  
> > > ###  
> > > class puppet::config {  
> > > include puppet::params  
> > > file { ''/etc/puppet/puppet.conf'':  
> > > ensure => present,  
> > > content =>
template(''puppet/puppet.conf.erb''),
> > > owner => ''root'',  
> > > group => ''admins'',  
> > > require => Class[''puppet::install''],  
> > > notify => Class[''puppet::service''],  
> > > }  
> > > }  
> > > ###  
> > >  
> > >  
> > > I''ve then got a manifest like this, which has a class
being included above:
> > > ###  
> > > class puppet::params {  
> > > $puppetserver = ''command.enterawesome.com
(http://command.enterawesome.com) (http://command.enterawesome.com)''
> > > }  
> > > ###  
> > >  
> > > The template being used in the first class includes the variable
> > > $puppetserver, but somehow, the include statement isn''t
enough for the
> > > variable to be defined within the scope of the manifest/template
> > > above.  
> > > What gives?  
> > > It works just fine if I include a statement like this in the erb
file:
> > > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
> > >  
> > > But I''d really like to understand scoping better. What
is it I need to
> > > do to just refer to the variable by name? Why isn''t the
include
> > > statement enough? Isn''t in including the puppet::params
class inside
> > > the puppet::config class, and therefore having the variable
defined in
> > > that context? Apparently not. But I don''t understand
why. I wan''t to
> > > end up at a point where the variable is in the proper scope, such
that
> > > I can just have a statement like <%= puppetserver %> inside
of the
> > > template I''m using.  
> > >  
> > > Thanks in advance!  
> > >  
> > > --  
> > > You received this message because you are subscribed to the
Google Groups "Puppet Users" group.
> > > To post to this group, send email to puppet...@googlegroups.com
(javascript:) (mailto:puppet...@googlegroups.com (javascript:)).
> > > To unsubscribe from this group, send email to
puppet-users...@googlegroups.com (javascript:)
(mailto:puppet-users+unsubscribe@googlegroups.com (javascript:)).
> > > For more options, visit this group at
http://groups.google.com/group/puppet-users?hl=en.
> >  
>  
> --  
> You received this message because you are subscribed to the Google Groups
"Puppet Users" group.
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devzero2000

2012-Aug-12 13:38 UTC

head link

Re: [Puppet Users] variable scoping?

On Sun, Aug 12, 2012 at 2:43 PM, Eric Shamow <eric@puppetlabs.com> wrote:
> First off, it''s important to distinguish import from include. They
"feel"
> like similar concepts but they''re not - import goes and physically
loads a
> file. Include says "ensure that this class is part of this
host''s resource
> graph."
>It is an import concept. It is very simple to think "include" in
puppet ="include" in C. No, they are much different
>
> It''s important not to think of Puppet in procedural, top-down
terms. We
> haven''t just said, "give me all the stuff in this class, and
now do these
> things." Rather we are building a model of a server, and manifest code
> simply informs pieces of that model. So by saying "include
<class>" you are
> really saying, "Puppet, if you haven''t already, make sure
this class is
> part of the overall resource graph."
>
> The better model for this example is, rather than a box inside of a box,
> you are looking at two sealed boxes sitting side by side. When you include
> the first group, it is added to the list of boxes used. Within the first
> box, when you then say "give me the second box," that second box
is placed
> *alongside* the first. Thus in order to grab anything from it, you have to
> specify "I need the stuff from box 2."
>
> Does that analogy help a bit more?
>
> The reason for this is that, as your number of classes grows, so too will
> your variables. If they share a single global namespace, the likelihood of
> a global variable name being used more than once increases. This can lead
> to really unexpected changes and ambiguity in building the graph.
>
> An example: suppose is this module you say $puppetmaster >
"myserver.local" and in another module, you want to only run on a
puppet
> master and so say $puppetmaster = true. When Puppet assembles the model of
> your system, which of the two is to be applied where? Dynamic scoping tried
> to guess at this. The idea here is to say, eliminate ambiguity - tell us
> exactly which one you want.
>
> In fact, this is the best analogy.  But clearly it is easy for everyone tomake mistakes especially if you are following the examples of "Pro
Puppet"
- incidentally, this book contains the same configuration discussed in this
thread that was valid for puppet 2.6 but it is not anymore for puppet 2.7

Best Regards
> -Eric
>
> --
>
> Eric Shamow
> Professional Services
> http://puppetlabs.com/
> ©631.871.6441
>
> Join us for PuppetConf 2012 at the Mission Bay Convention Center in San
> Francisco, California on September 27th and 28th -->
http://bit.ly/pcsig12
>
>
> On Sunday, August 12, 2012 at 2:35 AM, Zachary Alex Stern wrote:
>
> > So, your explanation makes sense to me - but that doesn''t
exactly
> explain to me why the "include" statement isn''t enough.
> >
> > E.g. when I''m "including the puppet::params class in the
puppet::config
> class, what affect is it having at all, if not setting things like the
> variables included in the original puppet::params class?
> >
> > How can I change variables on the fly effectively, if I can''t
just do
> the import and then have the variable $puppetserver equal the one from the
> imported class? I''m having a hard time grasping what import does,
if not
> this.
> >
> > On Saturday, August 11, 2012 10:36:48 PM UTC-4, Eric Shamow wrote:
> > > The best reference to explain how variable scoping works in
Puppet is
> this one -
> > >
> > > http://docs.puppetlabs.com/guides/scope_and_puppet.html
> > >
> > > Scoping has changed with 2.7, so you may find some confusing
> references online that follow the pre-2.7 rules. In general the 2.7 changes
> are designed to introduce some sanity to variable scopes and eliminate
> dynamic scoping, which causes all kinds of pain.
> > >
> > > The easiest way to think about scoping in general is that a scope
is
> defined by its container. If I put something physical in a box, I have
> access to it the moment I open the box, and other objects inside the box
> can interact with it. If, however, I now put that box inside a second box,
> the objects in the second box cannot interact directly with the objects in
> the first - the first object is protected by its container.
> > >
> > > Scoping mostly works the same way. The right way to get at the
> variable is to always explicitly scope, as you began to get at below with
> your scope.lookupvar example. As that can be a bit of a pain to repeat, you
> can always copy the value into a local variable:
> > >
> > > class puppet::config {
> > > include puppet::params
> > > $puppetserver = puppet::params::puppetserver
> > > …
> > > }
> > >
> > > -Eric
> > >
> > > --
> > >
> > > Eric Shamow
> > > Professional Services
> > > http://puppetlabs.com/
> > > ©631.871.6441
> > >
> > > Join us for PuppetConf 2012 at the Mission Bay Convention Center
in
> San Francisco, California on September 27th and 28th -->
> http://bit.ly/pcsig12
> > >
> > >
> > > On Saturday, August 11, 2012 at 8:45 PM, Zachary Stern wrote:
> > >
> > > > I''m having a really hard time grasping how
variables are scoped in
> > > > puppet (not really much of a programmer).
> > > >
> > > > I''ve got a manifest that looks like this:
> > > > ###
> > > > class puppet::config {
> > > > include puppet::params
> > > > file { ''/etc/puppet/puppet.conf'':
> > > > ensure => present,
> > > > content =>
template(''puppet/puppet.conf.erb''),
> > > > owner => ''root'',
> > > > group => ''admins'',
> > > > require => Class[''puppet::install''],
> > > > notify => Class[''puppet::service''],
> > > > }
> > > > }
> > > > ###
> > > >
> > > >
> > > > I''ve then got a manifest like this, which has a
class being included
> above:
> > > > ###
> > > > class puppet::params {
> > > > $puppetserver = ''command.enterawesome.com (
> http://command.enterawesome.com)
(http://command.enterawesome.com)''
> > > > }
> > > > ###
> > > >
> > > > The template being used in the first class includes the
variable
> > > > $puppetserver, but somehow, the include statement
isn''t enough for
> the
> > > > variable to be defined within the scope of the
manifest/template
> > > > above.
> > > > What gives?
> > > > It works just fine if I include a statement like this in the
erb
> file:
> > > > <%=
scope.lookupvar(''puppet::params::puppetserver'') %>
> > > >
> > > > But I''d really like to understand scoping better.
What is it I need
> to
> > > > do to just refer to the variable by name? Why isn''t
the include
> > > > statement enough? Isn''t in including the
puppet::params class inside
> > > > the puppet::config class, and therefore having the variable
defined
> in
> > > > that context? Apparently not. But I don''t
understand why. I wan''t to
> > > > end up at a point where the variable is in the proper scope,
such
> that
> > > > I can just have a statement like <%= puppetserver %>
inside of the
> > > > template I''m using.
> > > >
> > > > Thanks in advance!
> > > >
> > > > --
> > > > You received this message because you are subscribed to the
Google
> Groups "Puppet Users" group.
> > > > To post to this group, send email to
puppet...@googlegroups.com(javascript:) (mailto:
> puppet...@googlegroups.com (javascript:)).
> > > > To unsubscribe from this group, send email to
> puppet-users...@googlegroups.com (javascript:) (mailto:
> puppet-users+unsubscribe@googlegroups.com (javascript:)).
> > > > For more options, visit this group at
> http://groups.google.com/group/puppet-users?hl=en.
> > >
> >
> > --
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> https://groups.google.com/d/msg/puppet-users/-/LcHGaFjy9JkJ.
> > To post to this group, send email to
puppet-users@googlegroups.com(mailto:
> puppet-users@googlegroups.com).
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>
>
>
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>
>
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Zachary Stern

2012-Aug-13 15:31 UTC

head link

Re: [Puppet Users] variable scoping?

Ok, that''s helpful, however:

On Sun, Aug 12, 2012 at 8:43 AM, Eric Shamow <eric@puppetlabs.com> wrote:
> An example: suppose is this module you say $puppetmaster >
"myserver.local" and in another module, you want to only run on a
puppet
> master and so say $puppetmaster = true. When Puppet assembles the model of
> your system, which of the two is to be applied where? Dynamic scoping tried
> to guess at this. The idea here is to say, eliminate ambiguity - tell us
> exactly which one you want.

Sure, I get that, but I''m trying to do this within the module, not
globally.
Also imagine the following scenario.

I''ve configured the params.pp file to contain various things like
$puppet::params:puppetserver - but what if I want to override that in a
particular manfiest, but use the same template erb file for configuration.
I can''t, because I''ve used the scope.lookupvar tool in the
manifest, rather
than just doing <%= puppetserver %> and having that variable take on a
value based on context - not in terms of "dynamic scoping" but in
terms of
being able to, as discussed, include params.pp, or define it inside the
manifest that is using the template.

Is there any way to achieve this on-the-fly variable-changing, short of
using hiera or something like that? I''m just not there yet.

-- 

zachary alex stern I systems architect | ceo - enter: narnia

o: 212.731.2033 | f: 212.202.6488 | zs@enternewmedia.com

60-62 e. 11th street, 4th floor | new york, ny | 10003

www.enternewmedia.com

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Nan Liu

2012-Aug-13 16:33 UTC

head link

Re: [Puppet Users] variable scoping?

On Mon, Aug 13, 2012 at 8:31 AM, Zachary Stern <zs@enternewmedia.com>
wrote:
> Ok, that''s helpful, however:
>
>
> On Sun, Aug 12, 2012 at 8:43 AM, Eric Shamow <eric@puppetlabs.com>
wrote:
>
>> An example: suppose is this module you say $puppetmaster >>
"myserver.local" and in another module, you want to only run on a
puppet
>> master and so say $puppetmaster = true. When Puppet assembles the model
of
>> your system, which of the two is to be applied where? Dynamic scoping
tried
>> to guess at this. The idea here is to say, eliminate ambiguity - tell
us
>> exactly which one you want.
>
>
> Sure, I get that, but I''m trying to do this within the module, not
> globally.
> Also imagine the following scenario.
>
> I''ve configured the params.pp file to contain various things like
> $puppet::params:puppetserver - but what if I want to override that in a
> particular manfiest, but use the same template erb file for configuration.
> I can''t, because I''ve used the scope.lookupvar tool in
the manifest, rather
> than just doing <%= puppetserver %> and having that variable take on
a
> value based on context - not in terms of "dynamic scoping" but in
terms of
> being able to, as discussed, include params.pp, or define it inside the
> manifest that is using the template.
>
> Is there any way to achieve this on-the-fly variable-changing, short of
> using hiera or something like that? I''m just not there yet.
>
This is typically modeled via:

class puppet (
  $server = $puppet::params::server
) include puppet::params {
...
}

This allows any variables be overwritten in declaration, while allowing the
template to simply use $puppet::server. Most Puppet Labs forge modules use
this pattern, so take a look at them if you need a more complex example.

Nan

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Zachary Stern

2012-Aug-13 16:37 UTC

head link

Re: [Puppet Users] variable scoping?

> class puppet (
>   $server = $puppet::params::server
> ) include puppet::params {
> ...
> }
>
If I''m already specifying scope, e.g. $server =
$puppet::params::server,
why do I also need the include?



-- 

zachary alex stern I systems architect | ceo - enter: narnia

o: 212.731.2033 | f: 212.202.6488 | zs@enternewmedia.com

60-62 e. 11th street, 4th floor | new york, ny | 10003

www.enternewmedia.com

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Nan Liu

2012-Aug-13 16:42 UTC

head link

Re: [Puppet Users] variable scoping?

On Mon, Aug 13, 2012 at 9:37 AM, Zachary Stern <zs@enternewmedia.com>
wrote:
>
> class puppet (
>>   $server = $puppet::params::server
>> ) include puppet::params {
>> ...
>> }
>>
>
> If I''m already specifying scope, e.g. $server =
$puppet::params::server,
> why do I also need the include?
>
Sorry typo:

class puppet (
  $server = $puppet::params::server
) inherits puppet::params {
...

Nan

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Zachary Stern

2012-Aug-13 16:45 UTC

head link

Re: [Puppet Users] variable scoping?

On Mon, Aug 13, 2012 at 12:42 PM, Nan Liu <nan@puppetlabs.com> wrote:
> class puppet (
>   $server = $puppet::params::server
> ) inherits puppet::params {
>
Still missing something here - why do I need "inherits", or ANY
statement
at all, other than the $server = $puppet::params::server.
$puppet::params::server seems like it should be specific enough.

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Nan Liu

2012-Aug-13 17:52 UTC

head link

Re: [Puppet Users] variable scoping?

On Mon, Aug 13, 2012 at 9:45 AM, Zachary Stern <zs@enternewmedia.com>
wrote:> On Mon, Aug 13, 2012 at 12:42 PM, Nan Liu <nan@puppetlabs.com> wrote:
>>
>> class puppet (
>>   $server = $puppet::params::server
>> ) inherits puppet::params {
>
>
> Still missing something here - why do I need "inherits", or ANY
statement at
> all, other than the $server = $puppet::params::server.
> $puppet::params::server seems like it should be specific enough.
You don''t have access to variables in another class until you declare
or inherit from that class. This removes any ambiguity about the
values. This example might make it clearer why this is necessary:

class service::setting(
  $enable
) {
  if $enable {
    $status = ''on''
  } else {
    $status = ''off''
  }
}

So in this case the following manifests alone does not make any sense:

$status = $service::setting::status

The value of $service::setting::status can''t be determined until the
class is declared:

class { ''service::setting'':
  enable => true,
}

$status =  $service::setting::status

When puppet supports futures, this should give the same result:

$status =  $service::setting::status

class { ''service::setting'':
  enable => true,
}

However, as of today, because puppet compilation is order dependent,
only the second example works.

Thanks,

Nan

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Zachary Alex Stern

2012-Aug-14 15:56 UTC

head link

Re: [Puppet Users] variable scoping?

>
> Sorry typo:
>
> class puppet (
>   $server = $puppet::params::server
> ) inherits puppet::params {
>
>FWIW, this works:

 class puppet::config {

  include puppet::params
  $puppetserver=$puppet::params::puppetserver
  $runinterval=$puppet::params::runinterval
  file { ''/etc/puppet/puppet.conf'':
    ensure  => present,
    content => template(''puppet/puppet.conf.erb''),
    require => Class[''puppet::install''],
    notify  => Class[''puppet::service''],
    }
}

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Chad Huneycutt

2012-Aug-14 17:44 UTC

head link

Re: [Puppet Users] variable scoping?

On Tue, Aug 14, 2012 at 11:56 AM, Zachary Alex Stern
<zs@enternewmedia.com> wrote:>
> FWIW, this works:
>
>  class puppet::config {
>
>   include puppet::params
>   $puppetserver=$puppet::params::puppetserver
>   $runinterval=$puppet::params::runinterval
>   file { ''/etc/puppet/puppet.conf'':
>     ensure  => present,
>     content => template(''puppet/puppet.conf.erb''),
>     require => Class[''puppet::install''],
>     notify  => Class[''puppet::service''],
>     }
> }
So what if you would like to use a different puppet server?  You have
to go in to the module and change the params.pp file?  The code Nan
suggested allows you to override the value if necessary at the point
of inclusion, but fall back to a sane default specified in params.pp.
Personally, I am loving hiera, which provides even more flexibility:

class foo ( $bar = hiera(''bar'') ) {
...
}

And then $bar can be defined in a module-local class (if using puppet
hiera backend), module-local yaml file, site-specific yaml file,
overridden when included, etc, all according to a policy that you
define.

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Chad M. Huneycutt

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Zachary Stern

2012-Aug-14 18:12 UTC

head link

Re: [Puppet Users] variable scoping?

That''s a fair point, but not applicable to my use-case (multiple puppet
servers).

However, at some point in the near future, I''ll be using hiera, and
that
will be moot.

On Tue, Aug 14, 2012 at 1:44 PM, Chad Huneycutt
<chad.huneycutt@gmail.com>wrote:
> On Tue, Aug 14, 2012 at 11:56 AM, Zachary Alex Stern
> <zs@enternewmedia.com> wrote:
> >
> > FWIW, this works:
> >
> >  class puppet::config {
> >
> >   include puppet::params
> >   $puppetserver=$puppet::params::puppetserver
> >   $runinterval=$puppet::params::runinterval
> >   file { ''/etc/puppet/puppet.conf'':
> >     ensure  => present,
> >     content =>
template(''puppet/puppet.conf.erb''),
> >     require => Class[''puppet::install''],
> >     notify  => Class[''puppet::service''],
> >     }
> > }
>
> So what if you would like to use a different puppet server?  You have
> to go in to the module and change the params.pp file?  The code Nan
> suggested allows you to override the value if necessary at the point
> of inclusion, but fall back to a sane default specified in params.pp.
> Personally, I am loving hiera, which provides even more flexibility:
>
> class foo ( $bar = hiera(''bar'') ) {
> ...
> }
>
> And then $bar can be defined in a module-local class (if using puppet
> hiera backend), module-local yaml file, site-specific yaml file,
> overridden when included, etc, all according to a policy that you
> define.
>
> --
> Chad M. Huneycutt
>
> --
> You received this message because you are subscribed to the Google Groups
> "Puppet Users" group.
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>
>

-- 

zachary alex stern I systems architect

o: 212.731.2033 | f: 212.202.6488 | zs@enternewmedia.com

60-62 e. 11th street, 4th floor | new york, ny | 10003

www.enternewmedia.com

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jcbollinger

2012-Aug-15 13:51 UTC

head link

Re: [Puppet Users] variable scoping?

On Tuesday, August 14, 2012 1:12:12 PM UTC-5, Zachary Alex Stern
wrote:>
> That''s a fair point, but not applicable to my use-case (multiple
puppet
> servers).
>
> However, at some point in the near future, I''ll be using hiera,
and that
> will be moot.
>
To use multiple Puppet masters for the same site and retain your sanity, it 
is essential that all site-wide classes and data be automatically 
synchronized across the masters.  If the multiple servers are simply for 
scaling / load balancing, then obviously the entire Puppet config must be 
synchronized.  With these considerations in mind, I think the objection 
about modifying manifests is a red herring: if there is a synchronization 
issue there then it is an instance of a type of problem that should already 
have been solved.


John

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Zachary Stern

2012-Aug-15 15:06 UTC

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Re: [Puppet Users] variable scoping?

My point was that I don''t use and won''t be using multiple
puppet masters.

Also, at my current level of puppet knowledge, Nan''s code is basically
meaningless to me :(

On Wed, Aug 15, 2012 at 9:51 AM, jcbollinger
<John.Bollinger@stjude.org>wrote:
> To use multiple Puppet masters for the same site and retain your sanity,
> it is essential that all site-wide classes and data be automatically
> synchronized across the masters.



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www.enternewmedia.com

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Puppet users - Aug 2012 - variable scoping?

[Puppet Users] variable scoping?

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