Create nodes that do not share seeds, and give the clusters different names as a safety measure.
Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 6/03/2012, at 12:04 AM, Tamar Fraenkel wrote: > I want tow separate clusters. > Tamar Fraenkel > Senior Software Engineer, TOK Media > > <tokLogo.png> > > ta...@tok-media.com > Tel: +972 2 6409736 > Mob: +972 54 8356490 > Fax: +972 2 5612956 > > > > > > On Mon, Mar 5, 2012 at 12:48 PM, aaron morton <aa...@thelastpickle.com> wrote: > Do you want to create two separate clusters or a single cluster with two data > centres ? > > If it's the later, token selection is discussed here > http://www.datastax.com/docs/1.0/install/cluster_init#token-gen-cassandra > >> Moreover all tokens must be unique (even across datacenters), although - >> from pure curiosity - I wonder what is the rationale behind this. > Otherwise data is not evenly distributed. > >> By the way, can someone enlighten me about the first line in the output of >> the nodetool. Obviously it contains a token, but nothing else. It seems like >> a formatting glitch, but maybe it has a role. > It's the exclusive lower bound token for the first node in the ring. This > also happens to be the token for the last node in the ring. > > In your setup > 10.0.0.19 "owns" (85070591730234615865843651857942052864+1) to 0 > 10.0.0.28 "owns" (0 + 1) to 85070591730234615865843651857942052864 > > (does not imply primary replica, just used to map keys to nodes.) > > > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 5/03/2012, at 11:38 PM, Hontvári József Levente wrote: > >> You have to use PropertyFileSnitch and NetworkTopologyStrategy to create a >> multi-datacenter setup with two circles. You can start reading from this >> page: >> http://www.datastax.com/docs/1.0/cluster_architecture/replication#about-replica-placement-strategy >> >> Moreover all tokens must be unique (even across datacenters), although - >> from pure curiosity - I wonder what is the rationale behind this. >> >> By the way, can someone enlighten me about the first line in the output of >> the nodetool. Obviously it contains a token, but nothing else. It seems like >> a formatting glitch, but maybe it has a role. >> >> On 2012.03.05. 11:06, Tamar Fraenkel wrote: >>> Hi! >>> I have a Cassandra cluster with two nodes >>> >>> nodetool ring -h localhost >>> Address DC Rack Status State Load Owns >>> Token >>> >>> 85070591730234615865843651857942052864 >>> 10.0.0.19 datacenter1 rack1 Up Normal 488.74 KB >>> 50.00% 0 >>> 10.0.0.28 datacenter1 rack1 Up Normal 504.63 KB >>> 50.00% 85070591730234615865843651857942052864 >>> >>> I want to create a second ring with the same name but two different nodes. >>> using tokengentool I get the same tokens as they are affected from the >>> number of nodes in a ring. >>> >>> My question is like this: >>> Lets say I create two new VMs, with IPs: 10.0.0.31 and 10.0.0.11 >>> In 10.0.0.31 cassandra.yaml I will set >>> initial_token: 0 >>> seeds: "10.0.0.31" >>> listen_address: 10.0.0.31 >>> rpc_address: 0.0.0.0 >>> >>> In 10.0.0.11 cassandra.yaml I will set >>> initial_token: 85070591730234615865843651857942052864 >>> seeds: "10.0.0.31" >>> listen_address: 10.0.0.11 >>> rpc_address: 0.0.0.0 >>> >>> Would the rings be separate? >>> >>> Thanks, >>> >>> Tamar Fraenkel >>> Senior Software Engineer, TOK Media >>> >>> <Mail Attachment.png> >>> >>> >>> ta...@tok-media.com >>> Tel: +972 2 6409736 >>> Mob: +972 54 8356490 >>> Fax: +972 2 5612956 >>> >>> >>> >> > >
