Change Cluster an Storagecontainer from RF2 to RF3

 You can change your FT Level from 1N/1D to 2N/2D (if you have 5 or more Hosts) in the Prism GUI:

Then you have to change the RF at Storagecontainerlevel as well:

show all Container:

nutanix@NTNX-x:~$ ncli
<ncli> ctr list

Change RF to 3:

nutanix@NTNX-x:~$ ncli

<ncli> ctr edit name=CONTAINERNAME rf=3

for the Nutanix Management Share you have to login as admin:

nutanix@NTNX-x:~$ ncli -h true

<ncli> ctr update name=NutanixManagementShare rf=3 force=true