Github user aledsage commented on a diff in the pull request:
https://github.com/apache/brooklyn-docs/pull/78#discussion_r68120602
--- Diff: guide/ops/high-availability/high-availability-supplemental.md ---
@@ -0,0 +1,142 @@
+---
+title: High Availability (Supplemental)
+layout: website-normal
+---
+
+This document supplements the High Availability documentation available
[here](http://brooklyn.apache.org/v/latest/ops/high-availability.html)
+and provides an example of how to configure a pair of Apache Brooklyn
servers to run in master-standby mode with a shared NFS datastore
+
+### Prerequisites
+- Two VMs (or physical machines) have been provisioned
+- NFS or another suitable file system has been configured and is available
to both VMs*
+- An NFS folder has been mounted on both VMs at
`/mnt/brooklyn-persistence` and both machines can write to the folder
+
+\* Brooklyn can be configured to use either an object store such as S3, or
a shared NFS mount. The recommended option is to use an object
+store as described in the [Object Store
Persistence](./persistence/#object-store-persistence) documentation. For
clarity, a shared NFS folder
+is assumed in this example
+
+### Launching
+To start, download and install the latest Apache Brooklyn release on both
VMs following the 'OSX / Linux' section
+of the [Running Apache
Brooklyn](../start/running.html#install-apache-brooklyn) documentation
+
+On the first VM, which will be the master node, run the following to start
Brooklyn in high availability mode:
+
+{% highlight bash %}
+$ bin/brooklyn launch --highAvailability master --persist auto
--persistenceDir /mnt/brooklyn-persistence
+{% endhighlight %}
+
+Once Brooklyn has launched, on the second VM, run the following command to
launch Brooklyn in standby mode:
+
+{% highlight bash %}
+$ bin/brooklyn launch --highAvailability auto --persist auto
--persistenceDir /mnt/brooklyn-persistence
+{% endhighlight %}
+
+### Testing
+You can now confirm that Brooklyn is running in high availibility mode on
the master by logging into the web console at `http://<ip-address>:8081`.
+Similarly you can log into the web console on the standby VM where you
will see a warning that the server is not the high availability master.
+To test a failover, you can simply terminate the process on the first VM
and log into the web console on the second VM. Upon launch, Brooklyn will
--- End diff --
I'd add: If the master is terminated gracefully, the secondary will be
immediately promoted to mater. Otherwise, the secondary will be promoted after
heartbeats are missed for a given length of time. This defaults to thirty
seconds, and is configured in brooklyn.properties using
`brooklyn.ha.heartbeatTimeout`.
Perhaps miss out the `kill` command here - it's described in the docs that
@rdowner contributed (though without the `-9`)?
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