Re: Testing hot standby on same server sharing same tablespace directory - Mailing list pgsql-admin

From Sreekanth Palluru
Subject Re: Testing hot standby on same server sharing same tablespace directory
Date
Msg-id 4CCCD44C0EB1284FA34A4FDD88B7E4E8E649C5@abel.nb.superchoice.com.au
Whole thread Raw
In response to Re: Testing hot standby on same server sharing same tablespace directory  (Ian Barwick <ian@2ndquadrant.com>)
List pgsql-admin
Thanks Ian

-----Original Message-----
From: Ian Barwick [mailto:ian@2ndquadrant.com]
Sent: Thursday, 28 April 2016 11:55 AM
To: Sreekanth Palluru <Sreekanth.Palluru@superchoice.com.au>; pgsql-admin@postgresql.org
Subject: Re: [ADMIN] Testing hot standby on same server sharing same tablespace directory

On 04/28/2016 08:45 AM, Sreekanth Palluru wrote:
>
> Hi
>
> I am testing hot standby on same server (version 9.5.2) , everything works well.
> I have a doubt regarding sharing of tablespace directory by these two databases .
>
> I have created a tablespace and moved few objects and I happen to see
> that same directory was being used by standby node aka slave node and
> to my surprise it still works without any issues.
>
> Is this expected ?

Both instances will start and initially appear to function, but you are guaranteed to run into unexpected behaviour and
somekind of corruption. 

Try e.g. creating and populating a table, then pausing replay on the standby; then drop and recreate/repopulate the
sametable. 

> I was expecting some sort of warnings from Postgres or am I missing
> something

No, there's nothing which could warn about this particular scenario.


Regards

Ian Barwick


--
 Ian Barwick                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services


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