Add pre-network hook and example showing config-then-reboot

There are some requirements for early configuration that involves
e.g setting kernel parameters then rebooting.  Currently this can
be done via cloud-init, e.g firstboot templates, but there's been
discussion around enabling a SoftwareDeployment approach instead.

The main advantage of doing it this way is there's an error path
if something goes wrong with the config (except triggering the
reboot as we have to use NO_SIGNAL for that).

Change-Id: Ia54ee654f755631b8062eb5c209a60c6f9161500

1 files changed, 48 insertions, 0 deletions

diff --git a/extraconfig/pre_network/config_then_reboot.yaml b/extraconfig/pre_network/config_then_reboot.yaml
new file mode 100644
index 00000000..ec4d2761
--- /dev/null
+++ b/extraconfig/pre_network/config_then_reboot.yaml
@@ -0,0 +1,48 @@
+heat_template_version: 2014-10-16
+
+description: >
+  Do some configuration, then reboot - sometimes needed for early-boot
+  changes such as modifying kernel configuration
+
+parameters:
+  server:
+    type: string
+
+resources:
+
+  SomeConfig:
+    type: OS::Heat::SoftwareConfig
+    properties:
+      group: script
+      config: |
+        #!/bin/bash
+        echo "did some config before reboot" > /root/pre-reboot-config
+
+  SomeDeployment:
+    type: OS::Heat::SoftwareDeployment
+    properties:
+      name: SomeDeployment
+      server:  {get_param: server}
+      config: {get_resource: SomeConfig}
+      actions: ['CREATE'] # Only do this on CREATE
+
+  RebootConfig:
+    type: OS::Heat::SoftwareConfig
+    properties:
+      group: script
+      config: |
+        #!/bin/bash
+        # Stop os-collect-config to avoid any race collecting another
+        # deployment before reboot happens
+        systemctl stop os-collect-config.service
+        /sbin/reboot
+
+  RebootDeployment:
+    type: OS::Heat::SoftwareDeployment
+    depends_on: SomeDeployment
+    properties:
+      name: RebootDeployment
+      server:  {get_param: server}
+      config: {get_resource: RebootConfig}
+      actions: ['CREATE'] # Only do this on CREATE
+      signal_transport: NO_SIGNAL