Once Slony is installed and running on both nodes, we can actually make use of it and copy tables to a remote database. For high-availability PostgreSQL servers, making data available to external systems means long-running and potentially disruptive ad hoc queries no longer execute locally. It also means that reporting environments have direct copies of relevant tables and do not need to retrieve this data from our OLTP systems.
While OLTP servers can act as OLAP systems as well, these workloads are quite different. For the best performance possible and the least risk of outages, each server should be specialized. This recipe will use Slony to copy individual tables so we can decouple these two use cases.