From: legrand legrand <legrand_legrand@hotmail.com>
To: Laurenz Albe <laurenz.albe@cybertec.at>,
	"pgsql-general@lists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: =?Windows-1252?Q?Re=A0:_Fast_switchover?=
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Date: Tue, 9 Sep 2025 05:07:26 +0000
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Hi Laurenz,
Thank you for your answer

>> For some projects we need a fast manual switchover to address Near Zero =
downtime maintenance

I forgot to say that application would not be stopped during maintenance=85

>There is no need for synchronous replication; you cannot lose data with a =
switchover,
>if you do it right:

Ok

>> May logical replication ( bi-directional, with one instance RW and the o=
ther RO) be a better solution ?

> I'd say no.

Really ?

>> what could we expect (in term of downtime in both worlds) ?

> Usually seconds, so plan for ten minutes.

Brrr, I was th=EEnking about a more reliable process.

Regards
PAscal

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252">
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<div style=3D"font-family: inherit; font-size: inherit; color: inherit; bac=
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<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=
yle=3D"font-size:11pt" color=3D"#000000">Hi Laurenz,</font></div>
<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=
yle=3D"font-size:11pt" color=3D"#000000">Thank you for your answer</font></=
div>
<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=
yle=3D"font-size:11pt" color=3D"#000000"><br>
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<div class=3D"BodyFragment"><font size=3D"2"><span style=3D"font-size:11pt;=
">
<div class=3D"PlainText">&gt;&gt; For some projects we need a fast manual&n=
bsp;switchover to address Near Zero downtime maintenance<br>
<br>
I forgot to say that application would not be stopped during maintenance=85=
</div>
<div class=3D"PlainText"><br>
&gt;There is no need for synchronous replication; you cannot lose data with=
 a switchover,<br>
&gt;if you do it right:<br>
<br>
Ok<br>
<br>
&gt;&gt; May logical replication ( bi-directional, with one instance RW and=
 the other RO) be a better solution ?<br>
<br>
&gt; I'd say no.</div>
<div class=3D"PlainText"><br>
</div>
<div class=3D"PlainText">Really ?<br>
<br>
&gt;&gt; what could we expect (in term of downtime in both worlds) ?<br>
<br>
&gt; Usually seconds, so plan for ten minutes.<br>
<br>
</div>
<div class=3D"PlainText">Brrr, I was th=EEnking about a more reliable proce=
ss.</div>
<div class=3D"PlainText"><br>
</div>
<div class=3D"PlainText">Regards</div>
<div class=3D"PlainText">PAscal</div>
</span></font></div>
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