Sometimes we face situation like :

1. May need to remove some persistent attributes which we set a flag after some work is done
2. May be we set some attributes wrong so need to remove and reset the existing attribute.

The attribute may be set in attributes/default.rb OR insdie recipe with node normal attribute OR node set OR node override attributes.

There is a nice tool of chef (chef exec)  with which we can transform the attributes.

Usage:

Suppose a node with attribute hierarchy :

“normal” :[

{

“install_oradb” :  [

“is_installed” : “True”,

“is_running” :”True”

}

]

knife exec -E "nodes.transform(:all) {|n| n.normal_attrs[:install_oradb].delete(:is_installed) rescue nil }"

knife exec -E "nodes.transform(:all) {|n| n.normal_attrs[:install_oradb].delete(:is_running) rescue nil }"

 

Here we can replace normal_attrs with override_attrs OR default_attrs as required.

This will remove the attributes from all the nodes.

 

Suppose we want remove the attributes from a particular node. In this case you have to get search the node name from the chef solr index and replace the all with the required node.

e.g.

knife exec -E "nodes.transform(:node2) {|n| n.normal_attrs[:install_oradb].delete(:is_installed) rescue nil }"

knife exec -E "nodes.transform(:node2) {|n| n.normal_attrs[:install_oradb].delete(:is_running) rescue nil }"