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amuthan.arul_80414 avatar image
amuthan.arul_80414 asked ·

Not able to setup a second DC in DS210 course exercise

Hi ,

I am trying to Complete DS210 Exercise.Stuck with below one.

(Exercise: Stand-up a Second DC ) Not able to bring up Node in Second DC.

(Two Other nodes are running Fine).

root@ds210-node1:~# nodetool status
Datacenter: dc1
===============
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving/Stopped
-- Address Load Tokens Owns (effective) Host ID Rack
UN 172.18.0.2 17.58 MiB 8 47.2% 5fc95247-1e2f-4f56-96e1-d78f7e701a39 rack1
UN 172.18.0.3 13.45 MiB 8 52.8% 2a9ce3fa-d9f7-4729-91f5-f8abe0bb347b rack1

Node 2 Yaml Configuration information:-

cluster_name: 'KillrVideoCluster'
listen_address: 172.18.0.4
native_transport_address: 172.18.0.4
- seeds: "172.18.0.2"
num_tokens: 8
# initial_token:
endpoint_snitch: GossipingPropertyFileSnitch

Node 2 cassandra-rackdc.properties

# These properties are used with GossipingPropertyFileSnitch and will
# indicate the rack and dc for this node
dc=dc2
rack=rack1

Cassandra not started and Getting error when issuing nodetool command:-

root@ds210-node2:/etc/dse/cassandra# nodetool status
nodetool: Failed to connect to '127.0.0.1:7199' - ConnectException: 'Connection refused (Connection refused)'.

Cassandra running for few minutes and getting Down.

root@ds210-node2:/etc/dse/cassandra# sudo service dse status
* dse is not running
academyds210
2 comments
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Hi @amuthan.arul_80414,

could you check the system.log of the second node to see why it stops running after initially starting?

You should find the system.log in /var/log/cassandra directory. Check the last few log messages to see if this helps to understand why it stops running.

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amuthan.arul_80414 avatar image amuthan.arul_80414 bettina.swynnerton ♦♦ ·

system.txt

Not able to interrupt any useful information from system.log.

Attached last few lines and complete system log

INFO [main] 2020-08-07 21:55:28,886 DseConfig.java:409 - Cluster summary stats are not enabled
INFO [main] 2020-08-07 21:55:28,887 DseConfig.java:410 - Histogram data tables are not enabled
INFO [main] 2020-08-07 21:55:28,889 DseConfig.java:411 - User level latency tracking is not enabled
INFO [main] 2020-08-07 21:55:28,891 DseConfig.java:413 - Spark cluster info tables are not enabled
INFO [main] 2020-08-07 21:55:28,892 DseConfig.java:448 - Cql solr query paging is: off
INFO [main] 2020-08-07 21:55:28,894 DseConfig.java:452 - This instance appears to have 1 thread per CPU core and 2 total CPU threads.
INFO [main] 2020-08-07 21:55:28,900 DseConfig.java:469 - Server ID:02-42-AC-12-00-04
INFO [main] 2020-08-07 21:55:28,925 DseDaemon.java:612 - AlwaysOn SQL is not enabled
INFO [main] 2020-08-07 21:55:30,108 ColumnFamilyStore.java:440 - Initializing system.IndexInfo
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system.txt (122.1 KiB)
bettina.swynnerton avatar image
bettina.swynnerton answered ·

Hi @amuthan.arul_80414,

there isn't enough information in your original post to understand why the second nodes is not staying up after starting initially.

In this case, checking end of the system.log is a good first step. Misconfigurations for example would be called out with error messages in the logs. Without that information, it is difficult to advise you further here.

If this is still an issue, please update your initial post, we want to help you.

Cheers!

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Erick Ramirez avatar image
Erick Ramirez answered ·

To add to Bettina's answer, the log you attached indicates that you did not follow the exercise instructions correctly.

I have noted the following incorrect configurations from the log file:

INFO  [main] 2020-08-07 21:46:49,633  Config.java:595 - Node configuration:[ ... \
   broadcast_address=172.18.0.4; ... \
   cluster_name=TestCluster; ... \
   native_transport_broadcast_address=172.18.0.4; ... \
   seed_provider=org.apache.cassandra.locator.SimpleSeedProvider{seeds=172.18.0.2, 172.18.0.4}; ... \
]

My recommendation is you delete everything and start from scratch. Make sure you follow every single step in the instructions and pay attention to the details.

Finally, you need to apply what you've learned so far in DS201 and DS210 to troubleshoot your cluster. Instead of sending us the log file, you need to review it yourself. This is the whole point of the exercises. If we just give you the answers, you won't learn anything. Cheers!

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