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https://issues.apache.org/jira/browse/CASSANDRA-12296?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15567560#comment-15567560
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Kurt Greaves commented on CASSANDRA-12296:
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Yep, I didn't expect it to be correct. Just needed a starting point to get
someone talking about it.
Also:
{quote}If you're running NTS with only one replica, the patch will advise you
to consider NetworkTopologyStrategy{quote}
is not true, at least from my testing with rebuilds. This is because the
replica will always be in the specified DC, whereas with SimpleStrategy the
replica could potentially reside either in the current DC or another DC. When
else would this error message be triggered? I couldn't force this error message
to occur with repair, but maybe I'm missing something.
I can't see how SimpleStrategy would work if you take into account multiple
datacentres. If a user has 3 datacentres then an RF of 2 wouldn't be adequate.
It seems like there would be too many cases to cover to make a concise
recommendation to people.
> system_auth can't be rebuilt by default
> ---------------------------------------
>
> Key: CASSANDRA-12296
> URL: https://issues.apache.org/jira/browse/CASSANDRA-12296
> Project: Cassandra
> Issue Type: Bug
> Reporter: Jim Witschey
> Priority: Minor
> Labels: lhf
> Attachments: 12296.patch
>
>
> This came up in discussion of CASSANDRA-11687. {{nodetool rebuild}} was
> failing in a dtest. [~pauloricardomg] explained:
> bq. before [CASSANDRA-11848] the local node could be considered a source,
> while now sources are restricted only to dc2, so since {{system_auth}} uses
> {{SimpleStrategy}} depending on the token arrangement there could or not be
> sources from dc2. Fix is to either use
> {{-Dcassandra.consistent.rangemovement=false}} or update {{system_auth}} to
> use {{NetworkTopologyStrategy}} with 2 dcs..
> This is, at the very least, a UX bug. When {{rebuild}} fails, it fails with
> {code}
> nodetool: Unable to find sufficient sources for streaming range
> (-3287869951390391138,-1624006824486474209] in keyspace system_auth with
> RF=1.If you want to ignore this, consider using system property
> -Dcassandra.consistent.rangemovement=false.
> {code}
> which suggests that a user should give up consistency guarantees when it's
> not necessary.
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