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Zookeeper, mail # user - leader election, scheduled tasks, losing leadership


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Eric Pederson 2012-12-09, 04:17
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Jordan Zimmerman 2012-12-09, 04:25
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Eric Pederson 2012-12-09, 04:49
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Jordan Zimmerman 2012-12-09, 04:52
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Eric Pederson 2012-12-09, 04:54
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Re: leader election, scheduled tasks, losing leadership
Jordan Zimmerman 2012-12-09, 04:57
lol - I have an open bug for LeaderLatch. hasLeadership() is returning true when the cluster becomes unstable: https://github.com/Netflix/curator/issues/216 - In any event, you should register a ConnectionStateListener in case the cluster loses quorum.

-JZ

On Dec 8, 2012, at 8:54 PM, Eric Pederson <[EMAIL PROTECTED]> wrote:

> I am using Curator LeaderLatch :)
>
>
> -- Eric
>
>
>
> On Sat, Dec 8, 2012 at 11:52 PM, Jordan Zimmerman <
> [EMAIL PROTECTED]> wrote:
>
>> You might check your leader implementation. Writing a correct leader
>> recipe is actually quite challenging due to edge cases. Have a look at
>> Curator (disclosure: I wrote it) for an example.
>>
>> -JZ
>>
>> On Dec 8, 2012, at 8:49 PM, Eric Pederson <[EMAIL PROTECTED]> wrote:
>>
>>> Actually I had the same thought and didn't consider having to do this
>> until
>>> I talked about my project at a Zookeeper User Group a month or so ago
>> and I
>>> was given this advice.
>>>
>>> I know that I do see leadership being lost/transferred when one of the ZK
>>> servers is restarted (not the whole ensemble).   And it seems like I've
>>> seen it happen even when the ensemble stays totally stable (though I am
>> not
>>> 100% sure as it's been a while since I have worked on this particular
>>> application).
>>>
>>>
>>>
>>> -- Eric
>>>
>>>
>>>
>>> On Sat, Dec 8, 2012 at 11:25 PM, Jordan Zimmerman <
>>> [EMAIL PROTECTED]> wrote:
>>>
>>>> Why would it lose leadership? The only reason I can think of is if the
>> ZK
>>>> cluster goes down. In normal use, the ZK cluster won't go down (I assume
>>>> you're running 3 or 5 instances).
>>>>
>>>> -JZ
>>>>
>>>> On Dec 8, 2012, at 8:17 PM, Eric Pederson <[EMAIL PROTECTED]> wrote:
>>>>
>>>>> During the time the task is running a cluster member could lose its
>>>>> leadership.
>>>>
>>>>
>>
>>

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Eric Pederson 2012-12-09, 04:56
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Jordan Zimmerman 2012-12-09, 05:00
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Henry Robinson 2012-12-09, 05:02
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Jordan Zimmerman 2012-12-09, 05:04
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Henry Robinson 2012-12-09, 05:12
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Jordan Zimmerman 2012-12-09, 05:18
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Henry Robinson 2012-12-09, 05:30
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Jordan Zimmerman 2012-12-09, 05:41
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Eric Pederson 2012-12-09, 21:42
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Eric Pederson 2012-12-09, 22:10
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Vitalii Tymchyshyn 2012-12-10, 06:49
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Eric Pederson 2012-12-10, 11:52
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Vitalii Tymchyshyn 2012-12-11, 20:09
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Eric Pederson 2012-12-12, 00:54
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Henry Robinson 2012-12-09, 04:59
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Eric Pederson 2012-12-09, 05:00