On 17/07/2013, at 11:38 AM, Jeff Frost <[email protected]> wrote:

> I understand that it can't be demoted in the normal sense, I just expected it 
> to demote after migration-threshold failures were reached and not always on 
> the first failure.

Its a bit more subtle than you might imagine...

We don't just demote and re-promote a resource when the master fails.
It goes the through the full stop/start cycle too
 - which probably updates the promotion scores
 - which probably requires the PE to do some recalculations at a point the old 
master is stopped
 - at which point the promotion score for the old master is (and must) be 
ignored
 - which means a different node gets promoted instead

So its a reasonable expectation, its just not one we can currently live up to 
unfortunately.


> 
> BTW, the RA appears to work great, so thanks for your  work in this regard!
> 
> 
> On Jul 16, 2013, at 5:17 PM, Takatoshi MATSUO <[email protected]> wrote:
> 
>> Hi Jeff
>> 
>> The RA stops PostgreSQL on demote because PostgreSQL can't demote.
>> So it makes no sense to set migration-threshold when using pgsql RA
>> with replication.
>> 
>> I tried to restart PostgreSQL on demote, but it may cause data inconsistency.
>> It needs complicated mechanism to avoid it.
>> 
>> 
>> They say that PostgreSQL 9.4 may be able to avoid it in the future.
>> 
>> Thanks,
>> Takatoshi MATSUO
>> 
>> 2013/7/17 Jeff Frost <[email protected]>:
>>> Since I've been playing with the pgsql resource agent, it seems as though
>>> migration-threshold is ignored on the master node.
>>> 
>>> That is, when I stop the postgresql service on the master, it is immediately
>>> migrated even though migration-threshold is set to "30" in both the pgsql
>>> primitive and msPostgresql ms.
>>> 
>>> On the slave, it appears to act as expected.
>>> 
>>> Is it expected to act differently on the master or is there a different meta
>>> tag I should be using for master/slave clones?
> 
> 
> 
> 
> 
> 
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