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From Vikrant Singh <>
Subject Re: Query on SESSION_LOST (3.0.0)
Date Wed, 18 Nov 2015 23:13:25 GMT
Thanks a lot for reply. So if I am understanding it correct, there were
false alarms (or mistaken connection lost) . With 3.0.0 connection_lost
events will happen only when there is true session lost.

On Wed, Nov 18, 2015 at 1:16 PM, Cameron McKenzie <>

> Hey Vikrant,
> The issue was that the LOST event was being published by Curator when it
> gave up trying to reconnect to Zookeeper after connection loss, whereas
> most people were interpreting it to mean that the session was lost.
> So, the change in CURATOR-3.0 is that the LOST event will be published
> when the session has either expired and Curator is explicitly told this by
> Zookeeper (implying that a connection is present), or when Curator has been
> disconnected from Zookeeper for long enough for the session to have expired
> on the server (this will occur when no connection to Zookeeper is present).
> So, I'm not sure how it will help your case. It is just a more reliable
> way of knowing that the session is gone and all related ephemeral state on
> the Zookeeper server will also be gone.
> Note that it's also possible to tell Curator to use the legacy way of
> interpreting the LOST event.
> cheers
> On Thu, Nov 19, 2015 at 8:09 AM, Vikrant Singh <
>> wrote:
>> Hello All,
>> I need some guidance on understanding how to a fix done in latest release
>> 3.0.0 . I am talking about following fix -
>> .
>> In my project we create some ephemeral nodes and monitor a cluster
>> through a tree cache . Framework for treecache and ephemeral node is
>> created using ExponentialBackoffRetry with retry interval of 1 sec and
>> retry count of 29 (which is MAX_RETRIES_LIMIT ) .  We do kill the
>> process moment  we get TreeCacheEvent.Type.CONNECTION_LOST event .
>> As process restart is really expensive, I want to understand how I can
>> leverage from this fix.
>> Please help me in understanding what is the issue and how it may affect a
>> setup like ours. We are still not on 3.0.0.
>> Thanks,
>> Vikrant

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