Not heard of that before, chances are it's a problem in your code. Does machine A even know the other CF name? Can you log the batch mutations you are sending? When it appears in the other CF is the data complete?

There is also a Hector list, perhaps they can help.


On 10/02/2011, at 11:58 PM, Roland Gude <> wrote:



i am experiencing a strange issue. I have two applications writing to Cassandra (in different Column families in the same keyspace). The applications reside on different machines and know nothing about the existence of each other.

The both produce data and write it in Cassandra with batch mutations using hector.

So far so good, but it regularly happens, that data from one application ends up in columnfamilies reserved for the other application as well as the intended columnfamily.


Machine A writes to column family CF_A

Machine B writes to column families CF_B to CF_N


Regularly data that was written (According to my application logs) from Machine A to CF_A ends up in CF_A and in one of the other columnfamilies.


Any ideas why this could be happening?


I am using Cassandra 0.7.0 and hector 0.7.0-23








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