[ceph-users] As mon should be deployed in odd numbers, and I have a fourth node, can I deploy a fourth mds only? - 14.2.7

Presently I have about 1.2B objects (400M w/3 Replicas) and I'm finding the PG scrubbing and deep scrubbing are not completing. There is only 1 client accessing the data, a Samba server. I found large disparities in PG Distribution and Drive utilization. I enabled pg_autoscaler and found that it was reducing the number of PGs per OSD from 116 to 104.5 at this time, but it wasn't helping with space consumption equalization. I found loadbalancer and enabled that and it is in the process of evening out. As we were also having mds crashes even after increasing mds memory, i tried enabling multimds with rank:2 I currently have only 1 spare and would like to potentially enable the mds component on the fourth node (no mon present) but am having some difficulty. Is mon a requirement? I tried ceph-deploy mds create node4 but am having errors. I tried manually creating the /var/lib/ceph/mds/node4 directory and the command to create the keyring but still no joy. What am i missing? Thanks,