How to separate Ceph storage traffic in Proxmox
A homelab user shared how to properly split network traffic when running Ceph distributed storage on Proxmox. Keeping storage replication traffic on its own dedicated network prevents it from slowing down your virtual machines. This is not relevant for a single Mac mini, but useful context if you ever plan to add more nodes.
Proxmox is free, open-source software that lets you run multiple virtual machines on one computer or across several machines. Ceph is a storage system that pools the disks of multiple machines into one large shared drive. To work well, Ceph needs two separate networks: one for normal management and VM traffic, and a second dedicated one just for copying data between nodes (called replication).
If both types of traffic share the same network, Ceph's constant background replication can flood it and cause virtual machines to lag or the cluster to become unstable. For a single Mac mini setup, Ceph does not apply — it requires at least two or three machines. But if you ever plan to expand to a small cluster, it's worth knowing that network separation is a key step from the start.
Key points
- Ceph is a distributed storage system that merges disks from multiple servers into one shared pool
- Always use a separate dedicated network for Ceph replication traffic in Proxmox — never mix it with regular VM traffic
- Mixing traffic causes Ceph replication to overwhelm the shared network, slowing down everything else
- A single Mac mini does not need Ceph — it only makes sense with two or more machines in a cluster
- If you plan to expand your homelab into a cluster later, plan for multiple network interfaces early
Quick term guide
- replication
- The process of automatically copying data across multiple machines so that no data is lost if one machine fails.
- virtual machine
- A software-based computer that runs inside your real computer, letting you run a different operating system (like Linux) on your Mac.
- Mac mini
- A small desktop computer made by Apple.
- open-source software
- Software that is free for anyone to use, view, and change.
- open-source
- Software whose code is shared publicly so others can inspect, use, or change it.
- software
- Programs or apps that run on a computer or smartphone.
- network interface
- A virtual or physical connection point that lets a computer send and receive network data.
- Interface
- The visual parts of a program that a human interacts with.