[EDB](https://www.enterprisedb.com/) is pleased to announce the release of PG 
Failover Slots (pg_failover_slots). This database extension is released as open 
source software under the PostgreSQL license and is for anyone who has logical 
replication publications on Postgres databases that are also part of a 
Streaming Replication architecture. 

PG Failover Slots avoids the need for logical replication subscribers to reseed 
their logical replication tables when the logical replication publisher is part 
of a physical streaming replication architecture and a new Standby gets 
promoted to Primary. 

Since the replication slot used by logical replication is only maintained on 
the Primary node, downstream subscribers will not receive any new changes from 
the newly promoted Primary until the slot is created on the newly promoted 
Primary. Picking up logical replication changes from the newly promoted standby 
is unsafe because the information that includes which data a subscriber has 
confirmed receiving and which log data still needs to be retained for the 
subscriber will have been lost, resulting in an unknown gap in data. PG 
Failover Slots makes logical replication slots usable across a physical 
failover via the following features in the initial release:
* Copies any missing replication slots from the primary to the standby
* Removes any slots from the standby that aren't found on the primary
* Periodically synchronizes the position of slots on the standby based on the 
primary
* Ensures that selected standbys receive data before any of the logical slot 
walsenders can send data to consumers

You can find PG Failover Slots on 
[GitHub](https://github.com/EnterpriseDB/pg_failover_slots) along with the 
[Release 
notes](https://www.enterprisedb.com/docs/pg_extensions/pg_failover_slots/rel_notes/)
 at EDB Docs.

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