High Availability Routing for Postgres (HARP) v1.0
High Availability Routing for Postgres (HARP) is a cluster management tool for Bi-directional Replication (BDR) clusters. The core design of the tool is to route all application traffic within a data center to only one lead master at a time. A distributed consensus system is used to determine availability of the BDR nodes. On failure or unavailability of the lead master HARP determines a new lead master and changes application traffic routing accordingly.
Together with the core capabilities of BDR this mechanism of routing application traffic to the lead master node rules out split brain scenarios and allows for fast failover and switchover without risk of data loss.
HARP requires BDR Enterprise or BDR Standard versions 3.6 and 3.7.