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From Vikrant Singh <vikrant.subscr...@gmail.com>
Subject Re: Persistent Ephemeral Node
Date Mon, 12 Oct 2015 21:43:04 GMT
yeah I considered that.. but I ended up using tree cache because it gives
me more control on the state of tree . I have some custom handlers for
add/remove/update events. Same cache is also used for service discovery.

On Mon, Oct 12, 2015 at 2:33 PM, David Kesler <DKesler@yodle.com> wrote:

> There’s also already a Curator service discovery extension library that
> you can look at:  http://curator.apache.org/curator-x-discovery/index.html.
> It’s basically boiling down to the same strategy of sticking an ephemeral
> node into ZK, but with some additional convenience and functionality built
> on top of it.
>
>
>
> *From:* Cameron McKenzie [mailto:mckenzie.cam@gmail.com]
> *Sent:* Monday, October 12, 2015 5:05 PM
> *To:* user@curator.apache.org
> *Subject:* Re: Persistent Ephemeral Node
>
>
>
> hey Vikrant,
>
> Using a persistent ephemeral node just means that your application code
> doesn't need to worry about handling recreation of the node when it
> reconnects to ZooKeeper after connection / session loss.
>
>
>
> If your ephemeral node should always be present whenever your application
> instance is running, then this would be a good use case for a persistent
> ephemeral node.
>
> cheers
>
>
>
>
>
> On Tue, Oct 13, 2015 at 6:03 AM, Vikrant Singh <
> vikrant.subscribe@gmail.com> wrote:
>
> I have some basic question on persistent ephemeral node.
>
> Here is some background...
>
>
>
> We have a zoo keeper based service discovery setup. Each service register
> itself as a ephemeral node with zookeeper.When a service go down  its
> ephemeral node is removed from zookeeper and we know that service is down
> and we provision it again.
>
> At present we create plain ephemeral node. I am wondering what
> benefit/risks we may get if move to persistent ephemeral ones.  I see one
> problem... using  plane ephemeral node we can rely on state of ZK to make a
> decision like service is down. This is because we are sure that if a node
> get deleted with zoo keeper it will never comeback from same process. But
> if moved to "persistent ephemeral" I guess same may not be the case.
>
>
>
> Please let me know what you think of the same.
>
>
>
> Also I would like to know what are the best scenario where one should
> prefer using persistent ephemeral node over ephemeral node.
>
>
>
> Thanks,
>
> Vikrant
>
>
>

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