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MAPR rack topology

Question asked by rahul_mapr on Apr 18, 2018
Latest reply on Apr 19, 2018 by deborah

Hi Folks,

 

For our cluster below rack topology file is defined

# cat rack_topology.txt

File Contents

  1. 10.10.10.10 /data/mapr-rack1/node1
    10.10.10.20 /data/mapr-rack2/node1
    10.10.10.30 /data/mapr-rack3/node1
    10.10.10.40 /data/mapr-rack1/node2
    10.10.10.50 /data/mapr-rack2/node2
    10.10.10.10 /data/mapr-rack1/node1
    10.10.10.60 /data/mapr-rack3/node2
    10.10.10.70 /data/mapr-rack1/node3
    10.10.10.80 /data/mapr-rack2/node3
    10.10.10.90 /data/mapr-rack3/node3

Is this topology file correct?
What i assume is that there may be a case, where with default replication factor, all 3 replicas may be created on same rack, viz:

10.10.10.10 /data/mapr-rack1/node1
10.10.10.40 /data/mapr-rack1/node2
10.10.10.70 /data/mapr-rack1/node3

As mapr thinks, it to be three different racks configured.

In such cases, the whole purpose of rack topology gets defeated as ,all three replicas are on same physical rack(/data/mapr-rack1)
Please let me know if this assumption is correct as per my understanding?

 

Also, is mapr cluster rack aware in the sense that, client reads/writes data to node in a rack nearest to it?
Any document or official blog supporting it?


Regards,

Rahul Mishra

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