I guess at least for the OSGi world, not having a repository service
should solve the problem nicely.

Carsten

Am 18.08.15 um 12:24 schrieb Michael Marth:
> I think option b) would be not so bad - maybe by starting a commit hook that 
> denies any commit?
> (and screaming loudly in the logs)
> 
> 
> 
> 
> On 18/08/15 11:24, "Julian Reschke" <[email protected]> wrote:
> 
>> On 2015-08-18 11:14, Stefan Egli wrote:
>>> On 18/08/15 10:57, "Julian Reschke" wrote:
>>> ...
>>> Hi Julian,
>>>
>>> The idea is indeed that if an instance fails to update the lease then it
>>> will be considered by other instances in the cluster as dead/crashed -
>>> even though it still continues to function. It is the only one that is
>>> able to detect such a situation. Imv letting the instance shutdown is at
>>> this moment the only reasonable reaction as upper level code might
>>> otherwise continue to function on the assumption it is part of the cluster
>>> - to which the other instances do not agree, the others consider this
>>> instance as died.
>>>
>>> So taking one step back: the lease becomes a vital part of the functioning
>>> of Oak indeed.
>>>
>>> I see three alternatives:
>>>
>>> a) Oak itself behaves fail-safe and does the System.exit (that¹s the path
>>> I have suggested for now)
>>>
>>> b) Oak does not do the System.exit but refuses to update anything towards
>>> the document store (thus just throws exceptions on each invocation) - and
>>> upper level code detects this situation (eg a Sling Health Check) and
>>> would do a System.exit based on how it is configured
>>>
>>> c) same as b) but upper level code does not do a System.exit (I¹m not sure
>>> if that makes sense - the instance is useless in such a situation)
>>>
>>> d) none of the above and Oak tries to rejoin the cluster and continues to
>>> function (in my view this will not result in unmanageable edge cases)
>>> ...
>>
>> Yes, we need to think about how to stop Oak in this case. However I do 
>> not think that stopping the *VM* is something we can do here. Keep in 
>> mind that there might be many other things running in the VM which have 
>> nothing to do with the content repository.
>>
>> Best regards, Julian


-- 
Carsten Ziegeler
Adobe Research Switzerland
[email protected]

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