Merge pull request #3193 from carmstrong/preseed-deis

feat(contrib/coreos): add preseed script for Deis components

Author: carmstrong

contrib/coreos/user-data.example

@@ -127,6 +127,17 @@ write_files:
 
       # remove leading slash
       echo ${IMAGE#/}
+  - path: /run/deis/bin/preseed
+    permissions: '0755'
+    content: |
+      #!/bin/bash
+
+      COMPONENTS=(builder cache controller database logger logspout publisher registry router store-daemon store-gateway store-metadata store-monitor store-volume)
+
+      for c in $COMPONENTS; do
+        image=`/run/deis/bin/get_image /deis/$c`
+        docker history $image >/dev/null 2>&1 || docker pull $image
+      done
   - path: /opt/bin/deis-debug-logs
     permissions: '0755'
     content: |

docs/managing_deis/index.rst

@@ -19,6 +19,7 @@ Managing Deis
     operational_tasks
     platform_logging
     platform_monitoring
+    production_deployments
     recovering-ceph-quorum
     security_considerations
     ssl-endpoints

docs/managing_deis/production_deployments.rst

@@ -0,0 +1,58 @@
+:title: Production deployments
+:description: Considerations for deploying Deis in production.
+
+.. _production_deployments:
+
+Production deployments
+======================
+
+Many Deis users are running Deis quite successfully in production. When readying a Deis deployment
+for production workloads, there are some additional (but optional) recommendations.
+
+Preseeding containers
+---------------------
+
+When a host in your CoreOS cluster fails or becomes unresponsive, the CoreOS scheduler will relocate
+any cluster services on that machine to another host. These services come up on the new host just fine,
+but a component's first task is to pull the corresponding Docker image from Docker Hub. Depending
+on factors such as available bandwidth, network latency, and performance of the Docker Hub platform,
+this can take some time. Failover is not finished until the pull completes and the component starts.
+
+To minimize component downtime should failover occur, it is recommended to preseed the Docker images
+for Deis on all hosts in a cluster. This will pull all the images to the host's local Docker graph,
+so if failover should occur, a component can start quickly.
+
+A preseed script is provided as a script already loaded on CoreOS hosts.
+
+On all hosts in the cluster, run:
+
+.. code-block:: console
+
+    $ /run/deis/bin/preseed
+
+This will pull all component images for the installed version of Deis.
+
+Review security considerations
+------------------------------
+
+There are some additional security-related considerations when running Deis in production, and users
+can consider enabling a firewall on the CoreOS hosts as well as the router component.
+
+See :ref:`security_considerations` for details.
+
+Back up data
+------------
+
+Backing up data regularly is recommended. See :ref:`backing_up_data` for steps.
+
+Configure logging and monitoring
+--------------------------------
+
+Many users already have external monitoring or logging systems, and connecting Deis to these
+platforms is quite simple. Review :ref:`platform_logging` and :ref:`platform_monitoring`.
+
+Enable TLS
+----------
+
+Using TLS to encrypt traffic (including Deis client traffic, such as login credentials) is crucial.
+See :ref:`ssl-endpoints`.