I think it is reasonable that system keyspaces would get initialized with a default replication factor, assuming ones that were already initalized would remain intact (however, this should be the same for user-created keyspaces).
Assuming it doesn't change the current behaviour, and default and min rf, when unset, act the same way current version would, the only thing we should probably add is a line in cassandra.conf that default and min replication factors will also apply to system keyspaces. On Wed, May 13, 2020 at 9:01 PM Sumanth Pasupuleti < sumanth.pasupuleti...@gmail.com> wrote: > Hi, > > Based on Alex's suggestion on the ticket, wanted to reach out to clarify on > the current scope of default and minimum replication factors that 14557 > defines, and gather thoughts to farm for dissent. > > Both the configurations (default and minimum) apply not just to user > keyspaces, but also to system keyspaces. For instance, this can be handy in > deployments that use authenticated C* clusters where operators have to > "remember" to set system_auth keyspace's RF to a value higher than 1. In > such cases, setting default_rf = 3 for example (which I suppose is common > in most deployments) would ensure all the system keyspaces (including > system_auth) come up with RF=3. > > It can be helpful to note that, this patch by default does not cause any > change to the replication factors, reason being, the default values of > these configurations are set to [defaultRF=1, minimumRF=0] to not induce > any changes that folks may not expect, but rather offers knobs to define > what a sane default RF should be, and have a gate on any new keyspaces > being created with an RF lower than minimumRF. > > Curious to know your thoughts. > > Thanks, > Sumanth > -- alex p