Are there tickets/documents explain how data be replicated on Virtual Nodes? If there are multiple tokens on one physical host, may a chance two or more tokens chosen by replication strategy located on same host? If move/remove/add a token manually, does Cassandra Engine validate the case?
Thanks. On Jan 30, 2013, at 12:46 PM, Zhong Li wrote: >> You add a physical node and that in turn adds num_token tokens to the ring. > > No, I am talking about Virtual Nodes with order preserving partitioner. For > an existing host with multiple tokens setting list on cassandra.inital_token. > After initial bootstrapping, the host will not aware changes of > cassandra.inital_token. If I want add a new token( virtual node), I have to > rebuild the host with new token list. > > My question is if there is way to add a virtual nodes without rebuild it? > > Thanks, > > On Jan 30, 2013, at 10:21 AM, Manu Zhang wrote: > >> 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 <z...@voxeo.com >>>>> <mailto:z...@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. >
