Yes, which means that the ranges overlap each other.
Is this just a convention, or is it technically required when using
NetworkTopologyStrategy? Would it be acceptable to split the ranges
into quarters by ignoring the data centers, such as:
DC1
node 1 = 0 Range: (12, 16], (0, 0]
node 2 = 4 Range: (0, 4]
DC2
node 3 = 8 Range: (4, 8]
node 4 = 12 Range: (8, 12]
If this is OK, are there any drawbacks to this?
On 6/14/2011 6:10 PM, Vijay wrote:
Yes... Thats right... If you are trying to say the below...
DC1
Node1 Owns 50%
(Ranges 8..4 -> 8..5 & 8..5 -> 0)
Node2 Owns 50%
(Ranges 0 -> 1 & 1 -> 8..4)
DC2
Node1 Owns 50%
(Ranges 8..5 -> 0 & 0 -> 1)
Node2 Owns 50%
(Ranges 1 -> 8..4 & 8..4 -> 8..5)
Regards,
</VJ>
On Tue, Jun 14, 2011 at 3:47 PM, AJ <a...@dude.podzone.net
<mailto:a...@dude.podzone.net>> wrote:
This http://wiki.apache.org/cassandra/Operations#Token_selection
says:
"With NetworkTopologyStrategy, you should calculate the tokens the
nodes in each DC independantly."
and gives the example:
DC1
node 1 = 0
node 2 = 85070591730234615865843651857942052864
DC2
node 3 = 1
node 4 = 85070591730234615865843651857942052865
So, according to the above, the token ranges would be (abbreviated
nums):
DC1
node 1 = 0 Range: (8..4, 16], (0, 0]
node 2 = 8..4 Range: (0, 8..4]
DC2
node 3 = 1 Range: (8..5, 16], (0, 1]
node 4 = 8..5 Range: (1, 8..5]
If the above is correct, then I would be surprised as this
paragraph is the only place were one would discover this and may
be easy to miss... unless there's a doc buried somewhere in plain
view that I missed.
So, have I interpreted this paragraph correctly? Was this design
to help keep data somewhat localized if that was important, such
as a geographically dispersed DC?
Thanks!
