Re: Q: farsync questions
Date: Tue, 14 Oct 2014 12:49:09 +0200
Message-ID: <CALSQGrJ6VxxHpBZiSkbsZ+H06CmVX5ZvJeWt_rYFa0XYB20xOg_at_mail.gmail.com>
sorry, perhaps I misunderstand, you mean that you're not able to start FS anymore because of this error?
2014-10-14 12:44 GMT+02:00 amihay gonen <agonenil_at_gmail.com>:
> I want to simulate a situation where the FS has data not shipped to
> standby and primary is gone.
> now I've saw error complaining that the primary is not accessible ,that
> ok.
> But my simluation has a "twist" where the FS is also crashed .
>
> I don't understand although why the FS was looking for primary redo .
>
> btw ,I'm working in Max Availability (since I first "kill" the primary"
> and then the FS )
>
>
> On Tue, Oct 14, 2014 at 12:38 PM, Ludovico Caldara <
> ludovico.caldara_at_gmail.com> wrote:
>
>> Hi Amihay,
>> the FS will have errors since it has no connection to the primary. How
>> can the FS know if the primary is not alive and generating new redo? That's
>> the situation when you analyze the situation and take the risk of
>> activating the failover...
>> Having sync transport does not mean having complete recovery, the best
>> protection mode that you can achieve is Max Availability if you're using
>> far sync instances...
>>
>> If you look at the sequence# and block# of your RFS processes (or standby
>> log files)
>> you should have the last transactions and have those transactions sent
>> to the standby up to the same sequence/block. have you verified this?
>> you can check v$managed_standby view on the alive instances.
>>
>> Best regards
>> --
>> Ludo
>>
>>
>>
>> 2014-10-14 11:19 GMT+02:00 amihay gonen <agonenil_at_gmail.com>:
>>
>>> Hi all , I've started playing with farsync to learn better how it work.
>>>
>>> I've setup primary and farsync on the same instance (I know it is not
>>> best practice , but for learning propuse). I've create a standby on another
>>> machine and verified everything is working as expected.
>>>
>>> Then I've stop the standby (simluate network outage) , put some data in
>>> primary db + commit (no switch log ) and crash both primary db and farsync
>>> instance (in this order).
>>> After that , I've renamed the directory contains the primary db
>>> datafiles and redolog (simluate database loss)
>>>
>>> When starting the FS instance , i got errors in the alert log of the FS
>>> complaining it doesn't find the redologs of the primary !! .
>>>
>>> Any idea why ? it seems the FS read the primary redo log to complete
>>> recovery? this is strange to me since it is sync transport
>>>
>>>
>>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Tue Oct 14 2014 - 12:49:09 CEST