On Tue, Aug 9, 2011 at 10:07 AM, Evgeniy Ryabitskiy < evgeniy.ryabits...@wikimart.ru> wrote:
> > Rule of thumb, you should identify two servers in the cluster to be your >> seed nodes. >> >> >> > > Is this rule same for N node cluster? Any common practice/formula for seed > number? > Going to use about 10 nodes and extend it in a future. > > > > -- > Evgeniy Ryabitskiy > > This comes up a lot. All you really need to know is: 1) pick two (or more) nodes per data center as seed nodes. Having more does not hurt anything 2) sync the seed list to all your nodes Other things that are helpful. 3) seeds are used during startup to discover the cluster 4) newer versions of cassandra persist the cluster topology making seeds less important then they were in the 0.6.X series, where they were used every startup 5) You can make a seed a node at any time. There is nothing special about seed nodes. If you list the node in seed list it is a seed 6) seeds do not auto bootstrap (ie if a node has itself in its seed list it will not automatically transfer data to itself) If you want a node to do that bootstrap it first and then add it to seeds later. If you have no data (new install) you do not have to worry about bootstrap or autobootstrap at all.
