We are running Cassandra in AWS and On-Premise at customer sites, currently 2.1 in production with 3.0/3.11 in pre-production stages including loadtest.
In a migration path from 2.1 to 3.11.x, I’m afraid that at some point in time we end up in incremental repairs being enabled / ran a first time unintentionally, cause:
a) A lot of online resources / examples do not use the -full command-line option available since 2.2
b) Our internal (support) tickets of course also state nodetool repair command without the -full option, as these examples are for 2.1
Especially for On-Premise customers (with less control than with our AWS deployments), this asks a bit for getting out-of-control once we have 3.11 out and nodetool repair being run without the -full command-line option.
With troubles incremental repair are introducing and incremental being the default since 2.2 , what do you think about a JVM system property, cassandra.yaml setting or whatever … to basically let the cluster administrator chose if incremental repairs are allowed or not? I know, such a flag still can be flipped then (by the customer), but as a first safety stage possibly sufficient enough.