Thanks so much stewart U know, u are making the NDB Cluster technology more interesting for me.

Following ur response I have the following concerns;

Your best bet is to run the cluster on a private network with only the mysqlds visible to the outside world (where outside world=your web/application server (not the internet)). ===

Fine, I thought of this earlier yesterday.

And I also thought of encrypting the data that 'flows' over the network path
between the cluster engine and the NDBD nodes located on different physical m/c.

My reason for this is that; even if someone is able to break into the private
network (VLAN) where I am hosting the NDB Cluster, the data moving in-between
the NDBD nodes and the cluster engine cannot be 'sucked easily' or corrupted
(nor its integrity tampered with) becos it has been encrypted. Does MySQL
Cluster have capability for encryption of 'data in transit' between the cluster
engine to the NDBD nodes?

I need your detailed comment on this line of thought.

DataMemoryPerNode * (NumberOfNodes/NoOfReplicas) = Database size

e.g., you may have

200M * (4/N)= S

so with 2 replicas,

200M * (4/2)= 400M

(you may use up to 400mb for your database)

this should all be in the manual though. maybe it needs to be a bit clearer.

1)Is it safe to predetermine the size of my DataMemoryper Node when u probably
don't know how much data is going to be managed as transaction occurs.

2)I still have an issue here; What is the criteria for determining the optimum
number of NDBD nodes to configure for a single MySQL cluster installation?

it's how NDB works out how to implement the number of replicas you've asked for.

COGI

-- Stewart Smith, Software Engineer MySQL AB, www.mysql.com Office: +61 4 3 8844 332

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