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From Manu Zhang <owenzhang1...@gmail.com>
Subject Re: Understanding Virtual Nodes on Cassandra 1.2
Date Wed, 30 Jan 2013 15:21:36 GMT
On Wed 30 Jan 2013 02:29:27 AM CST, Zhong Li wrote:
> One more question, can I add a virtual node manually without reboot
> and rebuild a host data?
>
> I checked nodetool command, there is no option to add a node.
>
> Thanks.
>
> Zhong
>
>
> On Jan 29, 2013, at 11:09 AM, Zhong Li wrote:
>
>> I was misunderstood this
>> http://www.datastax.com/dev/blog/virtual-nodes-in-cassandra-1-2 ,
>> especially
>> "If you want to get started with vnodes on a fresh cluster, however,
>> that is fairly straightforward. Just don’t set the
>> |initial_token| parameter in your|conf/cassandra.yaml| and instead
>> enable the |num_tokens| parameter. A good default value for this is 256"
>>
>> Also I couldn't find document about set multiple tokens
>> for cassandra.inital_token
>>
>> Anyway, I just tested, it does work to set  comma separated list of
>> tokens.
>>
>> Thanks,
>>
>> Zhong
>>
>>
>> On Jan 29, 2013, at 3:06 AM, aaron morton wrote:
>>
>>>> After I searched some document on Datastax website and some old
>>>> ticket, seems that it works for random partitioner only, and leaves
>>>> order preserved partitioner out of the luck.
>>> Links ?
>>>
>>>>   or allow add Virtual Nodes manually?
>>> If not looked into it but there is a cassandra.inital_token startup
>>> param that takes a comma separated list of tokens for the node.
>>>
>>> There also appears to be support for the ordered partitions to
>>> generate random tokens.
>>>
>>> But you would still have the problem of having to balance your row
>>> keys around the token space.
>>>
>>> Cheers
>>> -----------------
>>> Aaron Morton
>>> Freelance Cassandra Developer
>>> New Zealand
>>>
>>> @aaronmorton
>>> http://www.thelastpickle.com <http://www.thelastpickle.com/>
>>>
>>> On 29/01/2013, at 10:31 AM, Zhong Li <zli@voxeo.com
>>> <mailto:zli@voxeo.com>> wrote:
>>>
>>>> Hi All,
>>>>
>>>> Virtual Nodes is great feature. After I searched some document on
>>>> Datastax website and some old ticket, seems that it works for
>>>> random partitioner only, and leaves order preserved partitioner out
>>>> of the luck. I may misunderstand, please correct me. if it doesn't
>>>> love order preserved partitioner, would be possible to add support
>>>> multiple initial_token(s) for  order preserved partitioner  or
>>>> allow add Virtual Nodes manually?
>>>>
>>>> Thanks,
>>>>
>>>> Zhong
>>>
>>
>

You add a physical node and that in turn adds num_token tokens to the 
ring.

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