@@ -709,8 +709,8 @@ HINT: To initiate replication, you must manually create the replication slot, e
709709 </para>
710710
711711 <para>
712- To confirm that the standby server is indeed ready for failover, follow these
713- steps to verify that allnecessary logical replication slots have been
712+ To confirm that the standby server is indeed ready for failover for a given subscriber , follow these
713+ steps to verify that allthe logical replication slots required by that subscriber have been
714714 synchronized to the standby server:
715715 </para>
716716
@@ -764,7 +764,7 @@ HINT: To initiate replication, you must manually create the replication slot, e
764764 Check that the logical replication slots identified above exist on
765765 the standby server and are ready for failover.
766766<programlisting>
767- /* standby # */ SELECT slot_name, (synced AND NOT temporary ANDNOT conflicting ) AS failover_ready
767+ /* standby # */ SELECT slot_name, (synced AND NOT temporary ANDinvalidation_reason IS NULL ) AS failover_ready
768768 FROM pg_replication_slots
769769 WHERE slot_name IN
770770 ('sub1','sub2','sub3', 'pg_16394_sync_16385_7394666715149055164');
@@ -782,10 +782,42 @@ HINT: To initiate replication, you must manually create the replication slot, e
782782 <para>
783783 If all the slots are present on the standby server and the result
784784 (<literal>failover_ready</literal>) of the above SQL query is true, then
785- existing subscriptions can continue subscribing to publications now on the
786- new primary server.
785+ existing subscriptions can continue subscribing to publications on the new
786+ primary server.
787+ </para>
788+
789+ <para>
790+ The first two steps in the above procedure are meant for a
791+ <productname>PostgreSQL</productname> subscriber. It is recommended to run
792+ these steps on each subscriber node, that will be served by the designated
793+ standby after failover, to obtain the complete list of replication
794+ slots. This list can then be verified in Step 3 to ensure failover readiness.
795+ Non-<productname>PostgreSQL</productname> subscribers, on the other hand, may
796+ use their own methods to identify the replication slots used by their
797+ respective subscriptions.
798+ </para>
799+
800+ <para>
801+ In some cases, such as during a planned failover, it is necessary to confirm
802+ that all subscribers, whether <productname>PostgreSQL</productname> or
803+ non-<productname>PostgreSQL</productname>, will be able to continue
804+ replication after failover to a given standby server. In such cases, use the
805+ following SQL, instead of performing the first two steps above, to identify
806+ which replication slots on the primary need to be synced to the standby that
807+ is intended for promotion. This query returns the relevant replication slots
808+ associated with all the failover-enabled subscriptions.
787809 </para>
788810
811+ <para>
812+ <programlisting>
813+ /* primary # */ SELECT array_agg(quote_literal(r.slot_name)) AS slots
814+ FROM pg_replication_slots r
815+ WHERE r.failover AND NOT r.temporary;
816+ slots
817+ -------
818+ {'sub1','sub2','sub3', 'pg_16394_sync_16385_7394666715149055164'}
819+ (1 row)
820+ </programlisting></para>
789821 </sect1>
790822
791823 <sect1 id="logical-replication-row-filter">
