Search code examples
chef-infrachef-recipetest-kitchenchef-template

How to preserve existing host file when running chef template resource

I'm trying to add new set of FQDN and IPs into the existing Windows hosts file by using the Chef template resources. What I found out is when I ran the chef recipe it will erase the existing hosts file and then add the new updates. I only want to append the new resources to the end of the file, am I doing something wrong here by using action :touch?

template file hosts.erb:

<% node['hostnames'].each do |name, value| %>
<%= value %>
<% end %>

recipe windows.rb file:

template 'C:\\Windows\\system32\\drivers\\etc\\hosts' do
  source 'hosts.erb'
  action :touch
end

kitchen converge output file tells me the hosts file is getting overwritten and not update? why?

   Recipe: hostnames::windows
     * template[C:\Windows\system32\drivers\etc\hosts] action touch
       - update content in file C:\Windows\system32\drivers\etc\hosts from 2d6bdf to 8068b4
       --- C:\Windows\system32\drivers\etc\hosts    2016-07-16 13:21:31.289888800 +0000
       +++ C:\Windows\system32\drivers\etc/chef-hosts20181128-568-1skk2oh   2018-11-28 01:15:55.998460000 +0000
       @@ -1,22 +1,6 @@
       -# Copyright (c) 1993-2009 Microsoft Corp.
       -#
       -# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
       -#
       -# This file contains the mappings of IP addresses to host names. Each
       -# entry should be kept on an individual line. The IP address should
       -# be placed in the first column followed by the corresponding host name.
       -# The IP address and the host name should be separated by at least one
       -# space.
       -#
       -# Additionally, comments (such as these) may be inserted on individual
       -# lines or following the machine name denoted by a '#' symbol.
       -#
       -# For example:
       -#
       -#      102.54.94.97     rhino.acme.com          # source server
       -#       38.25.63.10     x.acme.com              # x client host
       +# Content of the following hostnames are mainten by Chef cookbook

       -# localhost name resolution is handled within DNS itself.
       -#   127.0.0.1       localhost
       -#   ::1             localhost
       +10.219.33.1 a.us.bb-ops.io
       +10.219.34.2 b.us.bb-ops.io
       +10.219.35.3 c.us.bb-ops.io
       - update utime on file C:\Windows\system32\drivers\etc\hosts
Solution

  • This is proper Chef's behavior. You have two options: 1) Provide whole hosts file as atemplate or 2) Use FileEdit class, for example insert_line_if_no_match-instance_method.