cassandra - Periodically receive "InvalidQueryException: unconfigured columnfamily documents" -

we have app polling periodically changes every 1 minute, using datastax c* driver 2.0.4 (also tried 2.1.0-beta1).

we create session @ app startup, specifying keyspace, e.g. session session = cluster.connect("my_keyspace");

then using timer execute following selects every minute:

statement stmt = querybuilder.select().column("column2").from("my_keyspace","document_dates").where(querybuilder.in("key", date_keys)); resultset results = session.execute(stmt); 

and later:

stmt = querybuilder.select().from("my_keyspace","documents").where(querybuilder.in("key", rows.toarray(new object[rows.size()]))); results = session.execute(stmt); 

this seems work fine, except every 6 minutes see exception indicating "unconfigured columnfamily documents"

com.datastax.driver.core.exceptions.invalidqueryexception: unconfigured columnfamily documents     @ com.datastax.driver.core.exceptions.invalidqueryexception.copy(invalidqueryexception.java:35)     @ com.datastax.driver.core.defaultresultsetfuture.extractcausefromexecutionexception(defaultresultsetfuture.java:256)     @ com.datastax.driver.core.defaultresultsetfuture.getuninterruptibly(defaultresultsetfuture.java:172)     @ com.datastax.driver.core.abstractsession.execute(abstractsession.java:52)     @ com.mine.myclass$1.run(automodinserter.java:129)     @ java.util.timerthread.mainloop(timer.java:555)     @ java.util.timerthread.run(timer.java:505) caused by: com.datastax.driver.core.exceptions.invalidqueryexception: unconfigured columnfamily documents     @ com.datastax.driver.core.responses$error.asexception(responses.java:97)     @ com.datastax.driver.core.defaultresultsetfuture.onset(defaultresultsetfuture.java:108)     @ com.datastax.driver.core.requesthandler.setfinalresult(requesthandler.java:235)     @ com.datastax.driver.core.requesthandler.onset(requesthandler.java:367)     @ com.datastax.driver.core.connection$dispatcher.messagereceived(connection.java:584)     @ org.jboss.netty.channel.simplechannelupstreamhandler.handleupstream(simplechannelupstreamhandler.java:70)     @ org.jboss.netty.channel.defaultchannelpipeline.sendupstream(defaultchannelpipeline.java:564)     @ org.jboss.netty.channel.defaultchannelpipeline$defaultchannelhandlercontext.sendupstream(defaultchannelpipeline.java:791)     @ org.jboss.netty.channel.channels.firemessagereceived(channels.java:296)     @ org.jboss.netty.handler.codec.oneone.onetoonedecoder.handleupstream(onetoonedecoder.java:70)     @ org.jboss.netty.channel.defaultchannelpipeline.sendupstream(defaultchannelpipeline.java:564)     @ org.jboss.netty.channel.defaultchannelpipeline$defaultchannelhandlercontext.sendupstream(defaultchannelpipeline.java:791)     @ org.jboss.netty.channel.channels.firemessagereceived(channels.java:296)     @ org.jboss.netty.handler.codec.frame.framedecoder.unfoldandfiremessagereceived(framedecoder.java:462)     @ org.jboss.netty.handler.codec.frame.framedecoder.calldecode(framedecoder.java:443)     @ org.jboss.netty.handler.codec.frame.framedecoder.messagereceived(framedecoder.java:303)     @ org.jboss.netty.channel.simplechannelupstreamhandler.handleupstream(simplechannelupstreamhandler.java:70)     @ org.jboss.netty.channel.defaultchannelpipeline.sendupstream(defaultchannelpipeline.java:564)     @ org.jboss.netty.channel.defaultchannelpipeline.sendupstream(defaultchannelpipeline.java:559)     @ org.jboss.netty.channel.channels.firemessagereceived(channels.java:268)     @ org.jboss.netty.channel.channels.firemessagereceived(channels.java:255)     @ org.jboss.netty.channel.socket.nio.nioworker.read(nioworker.java:88)     @ org.jboss.netty.channel.socket.nio.abstractnioworker.process(abstractnioworker.java:108)     @ org.jboss.netty.channel.socket.nio.abstractnioselector.run(abstractnioselector.java:318)     @ org.jboss.netty.channel.socket.nio.abstractnioworker.run(abstractnioworker.java:89)     @ org.jboss.netty.channel.socket.nio.nioworker.run(nioworker.java:178)     @ org.jboss.netty.util.threadrenamingrunnable.run(threadrenamingrunnable.java:108)     @ org.jboss.netty.util.internal.deadlockproofworker$1.run(deadlockproofworker.java:42)     @ java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java:1145)     @ java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:615)     @ java.lang.thread.run(thread.java:722) 

i have seen few references keyspaces regards incorrectly specifying them in different clients, or using upper case chars requiring quotes, etc, nothing quite experiencing. i'm thrown frequency of exception not matching frequency of timer, still being predictable in happening every 6th iteration.

the closest thing have found unanswered question: unconfigured columnfamily error on consecutive execute calls (cql)

thanks advice