Proxmox + Ceph capacity calculator

Enter the cluster you are planning.

Cluster

Data protection

Net usable for VMs and containers
0TB
Raw installed
Storage efficiency
1 TB usable costs raw
Net usable Replica or parity copies Self-heal reserve Fill headroom
After protection only
Per Proxmox node
Total OSDs
Suggested pg_num
Behaviour under failure
Host failures survived without data loss
Host failures survived while still accepting writes
Data blocked if hosts fail at once
Raw data to recreate when one host dies
Utilisation after one host loss
Minimum nodes this profile needs
Recommended minimum for production
Nodes left after the planned reserve
Same hardware, other pool profiles
ProfileNet usable

How the number is built

Two assumptions worth checking