Hi! I have a 3 node cassandra cluster. I use Hector API. I give hecotr one of the node's IP address I call setAutoDiscoverHosts(true) and setRunAutoDiscoveryAtStartup(true).
The describe on one node returns:
Replication Strategy: org.apache.cassandra.locator.SimpleStrategy
Durable Writes: true
Options: [replication_factor:1]
The odd thing is that when I take one of the nodes down, expecting all to
continue running smoothly, I get exceptions of the format seen bellow, and
no read or write succeeds. When I bring the node back up, exceptions stop
and read and write resumes.
Any idea or explanation why this is the case?
Thanks!
me.prettyprint.hector.api.exceptions.HUnavailableException: : May not be
enough replicas present to handle consistency level.
at
me.prettyprint.cassandra.service.ExceptionsTranslatorImpl.translate(ExceptionsTranslatorImpl.java:66)
at
me.prettyprint.cassandra.service.KeyspaceServiceImpl$7.execute(KeyspaceServiceImpl.java:285)
at
me.prettyprint.cassandra.service.KeyspaceServiceImpl$7.execute(KeyspaceServiceImpl.java:268)
at
me.prettyprint.cassandra.service.Operation.executeAndSetResult(Operation.java:103)
at
me.prettyprint.cassandra.connection.HConnectionManager.operateWithFailover(HConnectionManager.java:246)
at
me.prettyprint.cassandra.service.KeyspaceServiceImpl.operateWithFailover(KeyspaceServiceImpl.java:131)
at
me.prettyprint.cassandra.service.KeyspaceServiceImpl.getSlice(KeyspaceServiceImpl.java:289)
at
me.prettyprint.cassandra.model.thrift.ThriftSliceQuery$1.doInKeyspace(ThriftSliceQuery.java:53)
at
me.prettyprint.cassandra.model.thrift.ThriftSliceQuery$1.doInKeyspace(ThriftSliceQuery.java:49)
at
me.prettyprint.cassandra.model.KeyspaceOperationCallback.doInKeyspaceAndMeasure(KeyspaceOperationCallback.java:20)
at
me.prettyprint.cassandra.model.ExecutingKeyspace.doExecute(ExecutingKeyspace.java:85)
at
me.prettyprint.cassandra.model.thrift.ThriftSliceQuery.execute(ThriftSliceQuery.java:48)
at
me.prettyprint.cassandra.service.ColumnSliceIterator.hasNext(ColumnSliceIterator.java:60)
at
*Tamar Fraenkel *
Senior Software Engineer, TOK Media
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ta...@tok-media.com
Tel: +972 2 6409736
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