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From "Laing, Michael" <michael.la...@nytimes.com>
Subject Re: Recommissioned node is much smaller
Date Sun, 07 Dec 2014 13:08:34 GMT
On a mac this works (different sed, use an actual newline):

"
nodetool info -T | grep ^Token | awk '{ print $3 }' | tr \\n , | sed -e
's/,$/\
>/'
"

Otherwise the last token will have an 'n' appended which you may not notice.

On Fri, Dec 5, 2014 at 4:34 PM, Robert Coli <rcoli@eventbrite.com> wrote:

> On Wed, Dec 3, 2014 at 10:10 AM, Robert Wille <rwille@fold3.com> wrote:
>
>>  Load and ownership didn’t correlate nearly as well as I expected. I have
>> lots and lots of very small records. I would expect very high correlation.
>>
>>  I think the moral of the story is that I shouldn’t delete the system
>> directory. If I have issues with a node, I should recommission it properly.
>>
>
> If you always specify initial_token in cassandra.yaml, then you are
> protected from some cases similar to the one that you seem to have just
> encountered.
>
> Wish I had actually managed to post this on a blog, but :
>
>
> --- cut ---
>
> example of why :
>
> https://issues.apache.org/jira/browse/CASSANDRA-5571
>
> 11:22 < rcoli> but basically, explicit is better than implicit
> 11:22 < rcoli> the only reason ppl let cassandra pick tokens is that it's
> semi-complex to do "right" with vnodes
> 11:22 < rcoli> but once it has picked tokens
> 11:22 < rcoli> you know what they are
> 11:22 < rcoli> why have a risky conf file that relies on implicit state?
> 11:23 < rcoli> just put the tokens in the conf file. done.
> 11:23 < rcoli> then you can use auto_bootstrap:false even if you lose
> system keyspace, etc.
>
> I plan to write a short blog post about this, but...
>
> I recommend that anyone using Cassandra, vnodes or not, always explicitly
> populate their initial_token line in cassandra.yaml. There are a number of
> cases where you will lose if you do not do so, and AFAICT no cases where
> you lose by doing so.
>
> If one is using vnodes and wants to do this, the process goes like :
>
> 1) set num_tokens to the desired number of vnodes
> 2) start node/bootstrap
> 3) use a one liner like jeffj's :
>
> "
> nodetool info -T | grep ^Token | awk '{ print $3 }' | tr \\n , | sed -e
> 's/,$/\n/'
> "
>
> to get a comma delimited list of the vnode tokens
>
> 4) insert this comma delimited list in initial_tokens, and comment out
> num_tokens (though it is a NOOP)
>
>  --- cut ---
>
> =Rob
>
>

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