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question

rht.rajput_193125 avatar image
rht.rajput_193125 asked ·

Why aren't my nodes in the DS201 course VM not showing in the right rack?

While i am running dsetool status, its showing incorrect rac name for 127.0.0.3.. even though i have it correct there.

ubuntu@ds201-node1:~$ /home/ubuntu/node2/bin/dsetool status
Warning: Not able to read Analytics Master data, SparkMaster data may not be correct.

DC: Cassandra Workload: Cassandra Graph: no
======================================================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Server ID Address Load Owns VNodes Rack Health [0,1]
DN 08-00-27-32-1E-DD 127.0.0.3 102.39 KiB ? 128 rack1 0.30

DC: east-side Workload: Cassandra Graph: no
======================================================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Server ID Address Load Owns VNodes Rack Health [0,1]
UN 08-00-27-32-1E-DD 127.0.0.2 126.3 KiB ? 128 hakuna-matata 0.30

DC: west-side Workload: Cassandra Graph: no
======================================================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Server ID Address Load Owns VNodes Rack Health [0,1]
UN 08-00-27-32-1E-DD 127.0.0.1 107.41 KiB ? 128 hakuna-matata 0.30
ubuntu@ds201-node1:~$ cat /home/ubuntu/node3/resources/cassandra/conf/cassandra-rackdc.properties | grep 'hakuna'
rack=hakuna-matata
ubuntu@ds201-node1:~$
academyds201
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1 Answer

bettina.swynnerton avatar image
bettina.swynnerton answered ·

Hi @rht.rajput_193125,

from this line in the output for 127.0.0.3 it looks like that you have not changed the snitch for this node:

DC: Cassandra Workload: Cassandra Graph: no

When the node is configured with DSESimpleSnitch, the datacenter name is inferred from the workload. In your case, the node runs a Cassandra workload, and the datacenter is named Cassandra for this reason.

When you use the DSESimpleSnitch, the cassandra-rackdc.properties file is ignored. This file has the information about datacenters and racks.

For the purpose of this exercise, stop cassandra on node3, clear the data from node3, change the snitch in the cassandra.yaml and make sure that your cassandra-rackdc.properties file has the correct setting, then restart the node, like you did for the other nodes in exercise 11 of dc201.

I hope this helps

Update: I should make it clear to change the snitch to GossipingPropertyFileSnitch

Thanks!


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