On 3/28/07, Alan Robertson <[EMAIL PROTECTED]> wrote:
Andrew Beekhof wrote:
>
> On Mar 22, 2007, at 2:13 AM, Alan Robertson wrote:
>
>> Doug Knight wrote:
>>> Hi Andrew,
>>> I had just started reviewing both of thes scripts, and reviewed the
>>> Multistate and clone resource pages on the web site. It looks like
>>> multistate is how I need to handle it, but a couple of questions first.
>>>
>>> 1. I noticed that the write-up says the resource must come up on each of
>>> the servers in "shadow" mode first, then one gets promoted. Does this
>>> imply a "start" on both servers, and the OCF start function determining
>>> which server is active vs shadow (I'm picturing a check in the OCF
>>> script to determine postgresql standby mode = shadow/crm_master value
>>> low, and postgresql active mode = active/crm_master value high), then a
>>> promote to the active server?
>>>
>>> 2. I noticed that the drbd OCF script contains a "notify" function,
>>> where the Stateful OCF script does not. The notify function looks to be
>>> where the important actions are taken (calling drbd_start_phase_2,
>>> pre/post, etc). Is the notify function necessary, or is it sufficient in
>>> my case to handle it through the start|stop|promote|demote functions?
>>>
>>> Thanks for your help,
>>> Doug
>>
>> Andrew's out for a while.
>>
>> The start function starts you up in slave/secondary mode. All resources
>> initially start up in "slave" mode.
>>
>> A set of servers is chosen to run the resources on (it might be one,
>> two, the whole set, etc. depending on clone_max and clone_node_max and
>> the usual constraints).
>>
>> They are started on the selected nodes using "start"
>>
>> During the start operation, you are given the chance to declare yourself
>> ready to become master or not by using the crm_master command line tool.
>>
>> I believe that your resource can run that command any time they like -
>> for example at a monitor operation... But, it is mandatory that they
>> run it when they first start up.
>
> mandatory in the sense that nothing will get promoted until someone,
> somewhere runs it.
> but the exact timing is completely up to the user/admin/RA... it is even
> possible to run it manually if you have to
I originally assumed what you said, but the docs contradict that by
calling it mandatory (and not qualifying the term). And the code seems
to indicate that you can ONLY run it from an RA.
if you know which OCF environment variables to set, then you can
potentially run it from anywhere... but most people wont need to run
it outside of the RA
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