err: Could not retrieve catalog from remote server: Error 400 on SERVER: Puppet::Parser::AST::Resource failed with error ArgumentError: Could not find declared class ABC at /etc/puppet/manifests/nodes.pp:14 on node XYZ

So this error is pretty confusing to understand at first glance,

err: Could not retrieve catalog from remote server: Error 400 on SERVER: Puppet::Parser::AST::Resource failed with error ArgumentError: Could not find declared class ABC at /etc/puppet/manifests/nodes.pp:14 on node XYZ

Basically it is kind of complaining on missing of specific modules ABC. There are 2 things could be checked here,

1. Make sure you have define the modulepath parameter per the document
http://docs.puppetlabs.com/puppet/2.7/reference/modules_fundamentals.html

2. Make sure you have properly define the class name within ABC/manifests/init.pp (well it happens to me couples of time and it turns out there was a typo within the init.pp)

So below init.pp is deemed to see the declared class not found error.


# cat /etc/puppet/modules/ABC/manifests/init.pp
class ABCtypo {

  exec { "blah ....":
       }

}