Minimizing Major Version Upgrade Downtime Utilizing Slony

Let's face it, major version upgrades can be a pain.  Most people are familiar with the
dump/restore method, but if your database happens to be larger than a few GB, the
downtime required for dump/restore is likely going to exceed your maximum maintenance
window.

We'll briefly explore upgrade options including dump/restore, pg_upgrade and
logical replication tools like Slony and why I think Slony is currently the
best option.  Then we'll run through a tutorial on how to use slony for
a major version upgrade with minimal downtime.