Usually, it’s a good practice to resemble the real datacenter in the Cassandra
topology, thus nodes mounted to distinct racks are know with different rack
names to Cassandra. This is due to the usual datacenter infrastructure, having
a single point of failure in each rack - e.g. a network switch
That doesn’t sound like a RHEL issue. Swapping can severely impact performance,
that’s why it is recommended to turn off swap on Cassandra nodes. This was
recommended in the Cassandra documentation by DataStax[1]. Apache Cassandra is
testing that and log a warning on startup [2] if swap is found
available anymore. The question now is whether this is a bug or do we have
another way to monitor the process?
Best regards,
Tibor Répási
