Re: Asynchronous streaming replication in postgresql

Can you elaborate on " Bad idea to do that automatically."

In production, that has to happen automatically, isn't it? There won't be an administrator available all the time to do a failover in case primary goes down..

-----Original Message-----
From: Simon Riggs [mailto:simon(at)2ndQuadrant(dot)com]
Sent: Friday, March 13, 2015 3:23 PM
To: Deole, Pushkar (Pushkar)
Cc: pgsql-cluster-hackers(at)postgresql(dot)org
Subject: Re: [pgsql-cluster-hackers] Asynchronous streaming replication in postgresql

On 12 March 2015 at 05:56, Deole, Pushkar (Pushkar) <pdeole(at)avaya(dot)com> wrote:

> I am new to postgreSql and evaluating the streaming replication for my
> use case. My use case is:
>
>
>
> 1. Need to replicate data from primary database (master) to secondary
> database (slave) asynchronously.
>
> 2. If master goes down, the slave should automatically be promoted to
> master.
>
> 3. Later, when the original primary server (original master) is
> brought up again, it should obtain back its master role and the new
> master should assume the slave again as it was with original setup.
>
>
>
> For #1, the streaming replication of postgresql is good enough.
>
> For #2, we need to create the trigger file in slave. This can be done
> manually. How can we do this automatically?

Look at repmgr, it does what you need.

> For #3, this seems to be quite complicated. Is this possible using
> streaming replication and if yes then how can this be achieved?

Bad idea to do that automatically.

--
Simon Riggs https://urldefense.proofpoint.com/v2/url?u=http-3A__www.2ndQuadrant.com_&d=AwIBaQ&c=BFpWQw8bsuKpl1SgiZH64Q&r=9JxdEvGq7qy3NnL3UxN47w&m=40Wa40JcHBzcpMHkes_PqVNhpVzn4pK5rDc4JEb1XcI&s=BTCgqd3RbpTPwz5yzUOwfvuP0p1OkgnFGfKcfF6BeDU&e=
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