[Pacemaker] MySQL/PostgreSQL HA cluster with Pacemaker

[Andrew Beekhof]

On Fri, Nov 2, 2012 at 2:34 AM, Andrew <nitr0 at seti.kr.ua> wrote:
> On 01/11/12 03:02, Andrew Beekhof wrote:
>>
>> On Thu, Nov 1, 2012 at 5:27 AM, Andrew<nitr0 at seti.kr.ua>  wrote:
>>>
>>> Hi all.
>>> I try to build 1+1 MySQL HA cluster, and currently I'm looking on Percona
>>> replication manager; other variant - to write own OCF for
>>> semi-synchronous
>>> master-slave replication. Also I want to run here PostgreSQL HA DB.
>>> So I have some questions:
>>> 1) How pacemaker decides what node should be master, when both nodes
>>> booting
>>> after, for ex., power failure? First running node will become a master,
>>> or
>>> Pacemaker can wait some time till node, that was a master before crash,
>>> will
>>> be running?
>>
>> We run monitor on both nodes.
>> This is the chance for the resource agent script to tell us their
>> preference for being promoted to master.
>> We then factor that into our decision.
>
> Can you explain? Pacemaker doesn't start master resource automatically if
> slave is booted succesfully and master is still booting/crashed at boot?

It does, but it first makes sure the failed node isn't running
anything by fencing it.

>
>>> 2) Is there a solution that may be better for data integrity?
>>> 3) What solutions are present for Postgres excluding classical DRBD
>>> solution?
>>>
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>>
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>
>
>
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