Dear Dojo community,

We have been running a cluster of 3 Cassandra nodes (running under Linux) for several months now and we recently hit a problem with one of the nodes where the /var directory ran out of disk space and crashed the Cassandra process. We cleared out some of the temp files in this directory and then restarted the VM. Afterwards we found that Cassandra would not restart and in the system.log file we find the error "CassandraDaemon.java:808 - Cannot start node if snitch's data center (dc1) differs from the previous data center (datacenter). Please fix the snitch configuration, decommission and rebootstrap this node or use the flag -Dcassandra.ignore_dc=true"

Our cassandra.yaml file has not been changed (file date from last year) and so we are confused why this is an issue? We are reluctant to start changing the configuration unless necessary and so any insight into the problem would be much appreciated.

Best regards,

Matt