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Usage of replication_factor > 1

See original GitHub issue

Maybe, it isn’t an issue, but misconfiguration or incorrect usage of replication.

cassandra-migrate-abc.yml

keyspace: abc
profiles:
  dev:
    replication:
      class: SimpleStrategy
      replication_factor: 2
migrations_path: ./migrations-abc

migrations-abc/v001-users.cql

CREATE TABLE abc.users (
    user_id text PRIMARY KEY,
    email text,
    first_name text,
    last_name text,
    phone text,
    roles text,
    status text,
    pwd_salt text,
    pwd_hash text
);

cassandra-migrate -H docker-dev -c cassandra-migrate-abc.yml -m dev migrate

And result:

Traceback (most recent call last):
  File "/usr/local/bin/cassandra-migrate", line 18, in <module>
    main()
  File "/Library/Python/2.7/site-packages/cassandra_migrate/cli.py", line 99, in main
    cmd_method(opts)
  File "/Library/Python/2.7/site-packages/cassandra_migrate/migrator.py", line 461, in migrate
    ignore_failed=opts.force)
  File "/Library/Python/2.7/site-packages/cassandra_migrate/migrator.py", line 263, in _verify_migrations
    'SELECT * FROM "{keyspace}"."{table}"'))
  File "/Library/Python/2.7/site-packages/cassandra_migrate/migrator.py", line 195, in _execute
    return self.session.execute(query, *args, **kwargs)
  File "cassandra/cluster.py", line 2016, in cassandra.cluster.Session.execute (cassandra/cluster.c:35491)
  File "cassandra/cluster.py", line 3826, in cassandra.cluster.ResponseFuture.result (cassandra/cluster.c:74365)
cassandra.cluster.NoHostAvailable: ('Unable to complete the operation against any hosts', {<Host: 10.133.0.20 europe-west1>: Unavailable('Error from server: code=1000 [Unavailable exception] message="Cannot achieve consistency level ALL" info={\'required_replicas\': 2, \'alive_replicas\': 1, \'consistency\': \'ALL\'}',)})

Issue Analytics

State:
Created 6 years ago
Comments:6 (2 by maintainers)

Top GitHub Comments

1reaction

holgerwcommented, Jul 13, 2017

@sierpito does your Cassandra development cluster consiste of 2+ nodes? I am not 100% sure, but it should be correct for Cassandra to fail with a keyspace creation, if the demanded replication_factor is larger then the number of nodes.

0reactions

sierpitocommented, Jul 14, 2017

Thank you. Closed.

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