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


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Re: leader election, scheduled tasks, losing leadership
Eric Pederson 2012-12-09, 04:54
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.
> >>
> >>
>
>