cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Marcus Olsson (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-9474) DC/Rack property changed on live system
Date Wed, 27 May 2015 07:32:17 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-9474?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14560563#comment-14560563
] 

Marcus Olsson commented on CASSANDRA-9474:
------------------------------------------

Yes, that's true, but for e.g. PropertyFileSnitch this could have some other benefits like
getting the DC/rack information for new nodes. One thing that's good about the reloading is
that you get some kind of negative response almost directly after changing the configuration,
which I think is better than getting it whenever that Cassandra instance is restarted since
that would be harder to trace back to the faulty configuration. Or better yet, to have DC
and rack configuration be a part of the sanity check at startup, which would make switching
DC/rack information harder, but still not impossible(update system.local).

> DC/Rack property changed on live system
> ---------------------------------------
>
>                 Key: CASSANDRA-9474
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-9474
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>         Environment: Cassandra 2.1.5
>            Reporter: Marcus Olsson
>             Fix For: 2.1.x
>
>
> When using GossipingPropertyFileSnitch it is possible to change the data center and rack
of a live node by changing the cassandra-rackdc.properties file. Should this really be possible?
In the documentation at http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeMultipleDS.html
it's stated that you should ??Choose the name carefully; renaming a data center is not possible??,
but with this functionality it doesn't seem impossible(maybe a bit hard with changing replication
etc.).
> This functionality was introduced by CASSANDRA-5897 so I'm guessing there is some use
case for this?
> Personally I would want the DC/rack settings to be as restricted as the cluster name,
otherwise if a node could just join another data center without removing it's local information
couldn't it mess up the token ranges? And suddenly the old data center/rack would loose 1
replica of all the data that the node contains.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message