[
https://issues.apache.org/jira/browse/ATLAS-511?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15187195#comment-15187195
]
venkata madugundu commented on ATLAS-511:
-----------------------------------------
>> I had a question on this. Seeing that trait definitions are also types and
>> are also cached in the
>> TypeSystem and that all lookups of traits happen from here, how frequently
>> are these CRUD'ed
>> in your case?
In our usecases (atleast from past experience), a notion like trait/tag has
been used more as a classification mechanism in business catalog/glossary. That
said, CRUD of trait is exposed as an application feature for end-user than
something which software uses for metadata classification using types. So in
that sense, traits are dynamic and their CRUD are driven by user of the
application quite frequently, whereas the types are static in that they define
the model for the metadata.
> Ability to run multiple instances of Atlas Server with automatic failover to
> one active server
> ----------------------------------------------------------------------------------------------
>
> Key: ATLAS-511
> URL: https://issues.apache.org/jira/browse/ATLAS-511
> Project: Atlas
> Issue Type: Sub-task
> Reporter: Hemanth Yamijala
> Assignee: Hemanth Yamijala
> Attachments: HADesign.pdf
>
>
> One of the most important components that only supports active-standby mode
> currently is the Atlas server which hosts the API / UI for Atlas. As
> described in the [HA
> Documentation|http://atlas.incubator.apache.org/0.6.0-incubating/HighAvailability.html],
> we currently are limited to running only one instance of the Atlas server
> behind a proxy service. If the running instance goes down, a manual process
> is required to bring up another instance.
> In this JIRA, we propose to have an ability to run multiple Atlas server
> instances. However, as a first step, only one of them will be actively
> processing requests. To have a consistent terminology, let us call that
> server the *master*. Any requests sent to the other servers will be
> redirected to the master.
> When the master suffers a partition, one of the other servers must
> automatically become the master and start processing requests. What this mode
> brings us over the current system is the ability to automatically failover
> the Atlas server instance without any manual intervention. Note that this
> can be arguably called an [active/active
> setup|https://en.wikipedia.org/wiki/High-availability_cluster]
> ATLAS-488 raised to support multiple active Atlas server instances. While
> that would be ideal, we have to learn more about the underlying system
> behavior before we can get there, and hopefully we can take smaller steps to
> improve the system systematically. The method proposed here is similar to
> what is adopted in many other Hadoop components including HDFS NameNode,
> HBase HMaster etc.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
