sling-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Dirk Rudolph (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (SLING-7830) Defined leader switch
Date Wed, 15 Aug 2018 12:12:00 GMT

    [ https://issues.apache.org/jira/browse/SLING-7830?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16580992#comment-16580992
] 

Dirk Rudolph commented on SLING-7830:
-------------------------------------

I agree on option 2 being more complex but for me this would be the favoured one. Lets say
we want to run with our blue-green deployment a zero-downtime strategy where the majority
of the users continue working on the green stack and a subset of samples working on the new
blue stack for verification. Having the master in the blue stack could cause a service interruption
for all users when an issue appears during verification. 

> Defined leader switch
> ---------------------
>
>                 Key: SLING-7830
>                 URL: https://issues.apache.org/jira/browse/SLING-7830
>             Project: Sling
>          Issue Type: Improvement
>          Components: Discovery
>            Reporter: Carsten Ziegeler
>            Priority: Major
>
> The current leader selection is based on startup time and sling id (mainly) and is stable
across changed in the topology for as long as the leader is up and running.
> However there are use cases like blue green deployment where new instances with a new
version are started and taking over the functionality. However with the current discovery
setup, the leader would still be one of the instances with the old version.
> With a new deployed version, tasks currently bound to the leader should run on the new
version.
> Therefore the leader needs to switch and stay the leader (until it dies).
> We probably need an additional criteria for the leader selection
> /cc [~egli]



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Mime
View raw message