cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Simone Franzini <>
Subject Re: UnknownColumnFamilyException after removing all Cassandra data
Date Tue, 07 Feb 2017 17:16:47 GMT
To further add to my previous answer, the node in question is a seed node,
so it did not bootstrap.
Should I remove it from the list of seed nodes and then try to restart it?

Simone Franzini, PhD

On Tue, Feb 7, 2017 at 9:43 AM, Simone Franzini <>

> This is exactly what I did on the second node. If this is not the correct
> / best procedure to adopt in these cases, please advise:
> 1. Removed all the data, including the system table (rm -rf data/
> commitlog/ saved_caches).
> 2. Configured the node to replace itself, by adding the following line to
> JVM_OPTS="$JVM_OPTS -Dcassandra.replace_address=<node
> own IP address>"
> 3. Start the node.
> Noticeably, I did not do nodetool decommission or removenode. Is that the
> recommended approach?
> Given what I did, I am mystified as to what the problem is. If I query the
> system.schema_columnfamilies on the affected node, all CF IDs are there.
> Same goes for the only other node that is currently up. Also, the other
> node that is currently up has data for all those CF IDs in the data folder.
> Simone Franzini, PhD
> On Tue, Feb 7, 2017 at 5:39 AM, kurt greaves <> wrote:
>> The node is trying to communicate with another node, potentially
>> streaming data, and is receiving files/data for an "unknown column family".
>> That is, it doesn't know about the CF with the id
>> e36415b6-95a7-368c-9ac0-ae0ac774863d.
>> If you deleted some columnfamilies but not all the system keyspace and
>> restarted the node I'd expect this error to occur. Or I suppose if you
>> didn't decommission the node properly before blowing the data away and
>> restarting.
>> You'll have to give us more information on what your exact steps were on
>> this 2nd node:
>> When you say deleted all Cassandra data, did this include the system
>> tables? Were your steps to delete all the data and then just restart the
>> node? Did you remove the node from the cluster prior to deleting the data
>> and restarting it (nodetool decommission/removenode? Did the node rejoin
>> the cluster or did it have to bootstrap?

View raw message