MIME-Version: 1.0
References: <CAA4eK1+AFY4E0f9h0-JF-navrf-vRMTMrN6H7PDKiR=C6p84Nw@mail.gmail.com>
 <CAJpy0uCcFKiofcp5V_hRvHrY_qVNX+eKvB0CPDNxSk2FbyMJCA@mail.gmail.com>
 <OS0PR01MB5716E731AC1B97A96B014B929460A@OS0PR01MB5716.jpnprd01.prod.outlook.com>
 <CAJpy0uDhR=m2Pr76aJZnvtKZpCEiLbMbjbPReCv5fS0MA3ch2w@mail.gmail.com>
 <CAJpy0uDWgSBUsTav1Eeo7E7i38GjXr_o0WdWamm3jGdctcoC4A@mail.gmail.com>
 <ZZa4pLFCe2mAks1m@ip-10-97-1-34.eu-west-3.compute.internal>
 <CAJpy0uBGSjwhZTBo6MxT6TkwO2AX5fa1kw7UC3RQLiapUJReuw@mail.gmail.com>
 <CAFiTN-vTaWUh0Eq8UpETMk=ZGFEMkD-1gXtosODZeCiCfi92kQ@mail.gmail.com>
 <CAA4eK1KLR2BP1GULkA9FMj3aKFbOcQLvu6b5fAht+YjCVRkc1w@mail.gmail.com>
 <CAFiTN-skn=ffyC8PMzg7gfpyNLfx7v9roae-+W8HYbpzoO0mkg@mail.gmail.com>
 <OS0PR01MB57169DD55EC8D9D1EDB7A0C2946A2@OS0PR01MB5716.jpnprd01.prod.outlook.com>
 <CAA4eK1L74EUU7+Dr11joY+Xact_MsjZu9G12sX+vRUWJsptP8Q@mail.gmail.com>
 <CAA4eK1+ORhnb2zUUpO_FcgWUUbwvQX5+=tdCehx7x2nB2x8VMg@mail.gmail.com>
 <CAD21AoCoX+jhy_i3v+T2s78NG_0HH1oXOUiTOWhDdxVPBtDHKA@mail.gmail.com>
 <CAJpy0uAwz9iNw3=5QC8S3z8Bf-w0z27rE32SFxjDMer7aTQMPg@mail.gmail.com>
 <CAA4eK1+q8R=yEpTMiOZ_Xksdd_Jg3SXvBMxRutHQtkCbdeK_yQ@mail.gmail.com>
 <CAJpy0uAU+nzufQwSzyB2YmhPHHn71_=1zkauP4Ra32a_eqbcig@mail.gmail.com>
 <CAA4eK1KtwFg6Mr1MRnHUUfPotzc2=5UCTq_D2t8x0PM1Lyhk8g@mail.gmail.com>
 <CAD21AoA03f0QKYjiSymGcnROvh1X-3YSqyB-19mkRXt5dfaxFw@mail.gmail.com>
 <CAJpy0uCneiKeNuz3B91Wf2LRxAenD3fpaxYfdL09y9qHmvVp+w@mail.gmail.com> <CAD21AoA5izeKpp9Ei4Cd745pKX3wn-TRvhhmPFEW9UY1nx+_aw@mail.gmail.com>
In-Reply-To: <CAD21AoA5izeKpp9Ei4Cd745pKX3wn-TRvhhmPFEW9UY1nx+_aw@mail.gmail.com>
From: Nisha Moond <nisha.moond412@gmail.com>
Date: Wed, 17 Jan 2024 10:41:42 +0530
Message-ID: <CABdArM73qdHyA0nteDLAQrfKNHRP+5Qq6p8uobg5bkE3EWiC+g@mail.gmail.com>
Subject: Re: Synchronizing slots from primary to standby
To: Masahiko Sawada <sawada.mshk@gmail.com>
Cc: shveta malik <shveta.malik@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, 
	"Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>, Dilip Kumar <dilipbalaut@gmail.com>, 
	Bertrand Drouvot <bertranddrouvot.pg@gmail.com>, Peter Smith <smithpb2250@gmail.com>, 
	"Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, 
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>, 
	Peter Eisentraut <peter.eisentraut@enterprisedb.com>, Bruce Momjian <bruce@momjian.us>, 
	Ashutosh Sharma <ashu.coek88@gmail.com>, Andres Freund <andres@anarazel.de>, 
	pgsql-hackers <pgsql-hackers@postgresql.org>, Ajin Cherian <itsajin@gmail.com>, 
	Alvaro Herrera <alvherre@alvh.no-ip.org>
Content-Type: text/plain; charset="UTF-8"
Archived-At: <https://www.postgresql.org/message-id/CABdArM73qdHyA0nteDLAQrfKNHRP%2B5Qq6p8uobg5bkE3EWiC%2Bg%40mail.gmail.com>
Precedence: bulk

A review on v62-006: failover-ready validation steps doc -

+       Next, check that the logical replication slots identified above exist on
+       the standby server. This step can be skipped if
+       <varname>standby_slot_names</varname> has been correctly configured.
+<programlisting>
+test_standby=# SELECT bool_and(synced AND NOT temporary AND
conflict_reason IS NULL) AS failover_ready
+               FROM pg_replication_slots
+               WHERE slot_name in ('sub');
+ failover_ready
+----------------
+ t
+(1 row)

This query does not ensure that all the logical replication slots
exist on standby. Due to the 'IN ('slots')' check, it will return
'true' even if only one or a few slots exist.