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Date: Mon, 16 Jan 2012 10:51:23 -0800
From: Manoj Govindassamy <manoj@nimblestorage.com>
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To: <pgsql-general@postgresql.org>, <pgsql-admin@postgresql.org>
Subject: PG synchronous replication and unresponsive slave
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anyone with PG Synchronous Replication knowledge, please help me with 
your views on the below questions.

thanks,
Manoj


On 01/12/2012 10:12 AM, Manoj Govindassamy wrote:
>
> any help on this is much appreciated.
>
> thanks,
> Manoj
>
>
> On 01/11/2012 01:50 PM, Manoj Govindassamy wrote:
>> Hi,
>>
>> I have a PG 9.1.2 Master <--> Slave with synchronous replication 
>> setup. They are all working fine as expected. I do have a case where 
>> I want to flip Master to non replication mode whenever its slave is 
>> not responding. I have set replication_timeout to 5s and whenever 
>> salve is not responding for for more than 5s, i see the master 
>> detecting it. But, the transactions on the master is stuck till the 
>> slave comes back. To get over it, I reloaded the config on master 
>> with synchronous_commit = local. Further transactions on the master 
>> are going thru fine with this local commits turned on.
>>
>> Here are my questions:
>>
>> 1. Transaction which was stuck right when slave going away never went 
>> thru even after I reloaded master's config with local commit on. I do 
>> see all new transactions on master are going thru fine, except the 
>> one which was stuck initially. How to get this stuck transaction 
>> complete or return with error.
>>
>> 2. Whenever there is a problem with slave, I have to manually reload 
>> master's config with local commit turned on to get master go forward. 
>> Is there any automated way to reload this config with local commit on 
>> on slave's unresponsiveness ? tcp connection timeouts, replication 
>> timeouts all detect the failures, but i want to run some corrective 
>> action on these failure detection.
>>
>
>