Originally from the User Slack
@SudeepSudeep**:** I have 12 nodes with replication factor of 3 and 3 racks. I want to change the replication factor to 2 because my cluster is running out of disk space. What is the best approach?
after changing the replication factor, does it make sense to move 4 nodes from rack c and move it to rack a and rack @Felipe_Cardeneti_Mendes?
@Felipe_Cardeneti_Mendes**:** well, best is to bootstrap new nodes so you can make more disk space, instead of reducing RF and risk losing quorum / read stale data 
that said, if you want to do this, then so long you’re aware of the side-effects, the general doc is https://docs.scylladb.com/manual/stable/kb/rf-increase.html which is also relevant to Decreasing it.
How to Safely Increase the Replication Factor | ScyllaDB Docs
remember to @Sudeepleanup after the change.
@Sudeep**:** thank you. It’s okay to keep 3 @Felipe_Cardeneti_Mendesacks after replication change?
@Felipe_Cardeneti_Mendes**:** yes
if you remove the “third” rack, then mathematics will hit y@Sudeepu and you’ll run close to out of disk space again :^)
@Sudeep**:** one more question? is it okay to run nodetool cleanup nodes at the same time. This cluster won’t serve any traffic.
@Felipe_Cardeneti_Mendes**:** yes