Make the container cache resolvers configurable

This change simply makes it possible for a deployer to change
the in container resolvers.

In the bootstrap-aio script the resolvers are being set in the
user_variables so containers are using the same resolvers as the
host.

Change-Id: Id7ab3632217c3eb2217a308d7226736a67900da5
Signed-off-by: Kevin Carter <kevin.carter@rackspace.com>

playbooks/roles/lxc_hosts/defaults/main.yml

@@ -81,6 +81,10 @@ lxc_cache_commands:
   - rm -f /usr/bin/python
   - ln -s /usr/bin/python2.7 /usr/bin/python
 
+lxc_cache_resolvers:
+  - 'nameserver 8.8.8.8'
+  - 'nameserver 8.8.4.4'
+
 lxc_cache_sshd_configuration:
     - { regexp: "^PermitRootLogin",         line: "PermitRootLogin yes" }
     - { regexp: "^TCPKeepAlive",            line: "TCPKeepAlive yes" }

playbooks/roles/lxc_hosts/tasks/lxc_cache_preparation.yml

@@ -22,6 +22,42 @@
     - lxc-cache
     - lxc-cache-update
 
+- name: Update container resolvers
+  template:
+    src: lxc-resolve-base.j2
+    dest: "{{ lxc_container_cache_path }}/{{ item.chroot_path }}/run/resolvconf/resolv.conf"
+  with_items: lxc_container_caches
+  tags:
+    - lxc-cache
+    - lxc-cache-update
+
+- name: Update container resolvconf base
+  template:
+    src: lxc-resolve-base.j2
+    dest: "{{ lxc_container_cache_path }}/{{ item.chroot_path }}/etc/resolvconf/resolv.conf.d/base"
+  with_items: lxc_container_caches
+  tags:
+    - lxc-cache
+    - lxc-cache-update
+
+- name: Update container resolvconf tail
+  copy:
+    content: "# Null Tail"
+    dest: "{{ lxc_container_cache_path }}/{{ item.chroot_path }}/etc/resolvconf/resolv.conf.d/tail"
+  with_items: lxc_container_caches
+  tags:
+    - lxc-cache
+    - lxc-cache-update
+
+- name: Update container resolvconf original
+  copy:
+    content: "# Null original"
+    dest: "{{ lxc_container_cache_path }}/{{ item.chroot_path }}/etc/resolvconf/resolv.conf.d/original"
+  with_items: lxc_container_caches
+  tags:
+    - lxc-cache
+    - lxc-cache-update
+
 # This task runs several commands against the cached image to speed up the
 # lxc_container_create playbook.
 - name: Prepare cached image

playbooks/roles/lxc_hosts/templates/lxc-resolve-base.j2

@@ -0,0 +1,3 @@
+{% for item in lxc_cache_resolvers %}
+{{ item }}
+{% endfor %}

scripts/bootstrap-aio.sh

@@ -275,6 +275,12 @@ if [ ! -d "/etc/openstack_deploy/conf.d" ];then
   mkdir -p "/etc/openstack_deploy/conf.d"
 fi
 
+# Ensure containers are using the same resolvers as the host
+RESOLVERS=$(grep nameserver /etc/resolv.conf | awk 'NF { print "\""$0"\""}' | tr '\n' ',' | sed 's/,$//' )
+if [ ! "$(grep -Rni '^lxc_cache_resolvers' /etc/openstack_deploy/user_variables.yml)" ]; then
+    echo "lxc_cache_resolvers: [$RESOLVERS]" | tee -a /etc/openstack_deploy/user_variables.yml
+fi
+
 # Add tempest settings for particular use-cases
 if [ ${DEPLOY_OPENSTACK} == "no" ]; then
   for svc in cinder glance heat horizon neutron nova; do