cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Robert Coli (JIRA)" <>
Subject [jira] [Commented] (CASSANDRA-5997) -D option to change cluster name
Date Thu, 12 Sep 2013 21:54:52 GMT


Robert Coli commented on CASSANDRA-5997:

My thinking is that we do not want a FAQ advising users to modify system keyspace manually.

If we, as a project, have made the decision that it is ok for users to do this, then ok. I
know that we have historically gone back and forth on even *allowing* them to do so. My understanding
is we now allow them to do so, except for certain columnfamilies, but I'm not clear on why?
It seems really quite dangerous as a general concept, and I personally am uncomfortable with
advising average users to do so.

However if the project goes on record as being explicitly ok with this, both generally and
in specific, I'm fine with it from a practical perspective.
> -D option to change cluster name
> --------------------------------
>                 Key: CASSANDRA-5997
>                 URL:
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Robert Coli
>            Priority: Minor
> A steady trickle of users have a need to change the name of their cluster. Perhaps they
accidentally started their cluster with the wrong name and now want to change it.
> Has the old recommendation, which was to edit the cluster name in LocationInfo and then
> Has the old workaround, which was to remove LocationInfo CF entirely.
> As this info now lives in a column called "cluster_name" in a row with key "local" in
a CF called "local" in the keyspace "system", one can no longer simply nuke LocationInfo.
The only workaround remaining is to nuke the entire system Keyspace and re-coalesce the cluster,
and then reload schema.
> The community continues to need to perform this operation and we do not want to tell
them to nuke or manually modify the system keyspace (though it seems they have perms again
to modify..). This ticket requests a new startup -D flag "-Dcassandra.new_cluster_name" which
allows one to overwrite this value at startup time. This means a rolling restart will accomplish
the "rename my cluster" task, with only the cost of split-cluster for the duration.

This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see:

View raw message