rng_dev_path in nova.conf template configurable in node attribute

added attribute to make rng_dev_path in nova.conf configurable with the
node attribute default['openstack']['compute']['libvirt']['rng_dev_path']. Default is set to nil to let this parameter stay an optional one.

Change-Id: I1bcf67eec0b8918a3ba644d76cafb20ab89ce704

CHANGELOG.md

@@ -6,6 +6,7 @@ This file is used to list changes made in each version of cookbook-openstack-com
 * Upgrading to Juno
 * Sync conf files with Juno
 * Upgrading berkshelf from 2.0.18 to 3.1.5
+* rng_dev_path in nova.conf configured from node attribute
 
 ## 9.3.1
 * Move auth configuration from api-paste.ini to nova.conf

README.md

@@ -249,6 +249,7 @@ Libvirt Configuration Attributes
 * `openstack["compute"]["libvirt"]["live_migration_uri"]` - Migration target URI (any included "%s" is replaced with the migration target hostname).
 * `openstack["compute"]["libvirt"]["rbd"]["rbd_user"]` - The cephx user used for accessing the RBD pool used for block storage. (Which pool to use is passed by cinder when nova-compute is instructed to mount a volume.)
 * `openstack["compute"]["libvirt"]["rbd"]["rbd_secret_name"]` - The name of the databag item containing the UUID shared between Cinder and nova-compute.  `libvirt_rbd` will define a libvirt secret with this UUID, containing the `rbd_user`'s password.  The password itself will be retrieved using `get_password` on the service `rbd_block_storage`.  Creating the cephx user in a Ceph cluster has to be done outside of the scope of this cookbook.
+* `openstack["compute"]["libvirt"]["rng_dev_path"]` - A path to a device that will be used as source of entropy on the host. Permitted options are: /dev/random or /dev/hwrng (string value)
 
 Scheduler Configuration Attributes
 ----------------------------------

attributes/default.rb

@@ -216,6 +216,8 @@ default['openstack']['compute']['libvirt']['unix_sock_rw_perms'] = '0770'
 default['openstack']['compute']['libvirt']['libvirt_inject_key'] = true
 default['openstack']['compute']['libvirt']['libvirt_inject_password'] = false
 default['openstack']['compute']['libvirt']['libvirt_inject_partition'] = -2
+# A path to a device that will be used as source of entropy on the host. Permitted options are: /dev/random or /dev/hwrng (string value)
+default['openstack']['compute']['libvirt']['rng_dev_path'] = nil
 # VM Images format. Acceptable values are: raw, qcow2, lvm,
 # rbd, default. If default is specified, then use_cow_images
 # flag is used instead of this one. (string value)

spec/nova-common_spec.rb

@@ -69,6 +69,15 @@ describe 'openstack-compute::nova-common' do
         )
       end
 
+      it 'has no rng_dev_path by default' do
+        expect(chef_run).not_to render_file(file.name).with_content(/^rng_dev_path=/)
+      end
+
+      it 'has rng_dev_path config if provided from attribute' do
+        node.set['openstack']['compute']['libvirt']['rng_dev_path'] = '/dev/random'
+        expect(chef_run).to render_file(file.name).with_content(%r{^rng_dev_path=/dev/random$})
+      end
+
       it 'has dnsmasq_config_file' do
         expect(chef_run).to render_file(file.name).with_content(/^dnsmasq_config_file=$/)
       end

templates/default/nova.conf.erb

@@ -542,7 +542,9 @@ disk_cachemodes=<%= node["openstack"]["compute"]["config"]["disk_cachemodes"] %>
 # A path to a device that will be used as source of entropy on
 # the host. Permitted options are: /dev/random or /dev/hwrng
 # (string value)
-#rng_dev_path=<None>
+<% if node["openstack"]["compute"]["libvirt"]["rng_dev_path"] -%>
+rng_dev_path=<%= node["openstack"]["compute"]["libvirt"]["rng_dev_path"] %>
+<% end -%>
 
 #
 # Options defined in nova.virt.libvirt.imagecache