I think your response in this mail thread works for this use case:

http://mail-archives.apache.org/mod_mbox/helix-user/201308.mbox/browser

Thanks,
Venkat

________________________________
From: Krishnamoorthy, Venkata
Sent: 2014, July, 29 4:34 PM
To: [email protected]
Subject: RE: Fencing

Hi Kishore,

Sorry abt the late response. The usecase is as follows:

If multiple replicas of a partition has access to a common resource such as 
coherence cache or a databaseassuming that some kind of locking is required at 
the application level to do write update, if one of the replicas becomes 
offline from the point of Helix, then the particular replica needs to be 
forcibly restarted to avoid starvation for other replicas.

I was wondering if this requirement can be achieved through Fencing concept 
using Helix.

Thanks,
Venkat
________________________________
From: kishore g [mailto:[email protected]]
Sent: 2014, July, 24 3:24 PM
To: [email protected]
Subject: Re: Fencing

Hi Venkat,

We don't have explicit support for fencing. We provide some callbacks that can 
be used to deal with such scenarios. Can you give us more info on the scenario. 
What state model are you using, what is the shared resource and when you say 
unresponsive what could be the likely cause(e.g. GC).

thanks,
Kishore G


On Thu, Jul 24, 2014 at 9:57 AM, Krishnamoorthy, Venkata 
<[email protected]<mailto:[email protected]>> 
wrote:
Is there support for Fencing ( http://en.wikipedia.org/wiki/Fencing_(computing) 
) in Helix? If not, how do I implement this feature to make sure that a 
participant that is not responsive is actually shutdown in order to avoid 
wrongful access to shared resources and race conditions? Please let me know.

Thanks,
Venkat




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