Proxmox + Ceph: Single Node Installation for Test Lab or Home Setup

Run Ceph on One Node in Proxmox – Is It Possible? Here’s How

Let say you have a single machine Proxmox VE and have several harddisk. Let say the total of disk are 4 disks. 1 disk for OS, and 3 disks for ceph OSD.

I am newbie and I want to know how to install and configure Ceph on Proxmox VE.

This guide will explain how to install Ceph cluster directly on single Proxmox VE machine. With this approach, you only need 2 machine if you want to try Ceph RBD Mirroring

If you want to install a Ceph cluster on a single machine using different OS, please check this guide: “How to Set Up a Ceph Cluster on a Single Node”

# Install and Configure Ceph

Go to Datacenter | PVE Host | Ceph | Install/Configure Ceph. You can use reef or squid (latest) for ceph version. Next and Finish

# Add OSD

Go to Datacenter | PVE Host | Ceph | OSD | Create: OSD

Select available disk one by one to create OSD

# Monitoring Ceph

Go to Datacenter | PVE Host | Ceph. You will see the Ceph status like below. The Ceph status is HEALTH_WARN

# Reconfigure crush map

From CLI, Do the following process

Extract crush map:

ceph osd getcrushmap -o crushmap.cm

Decompile crushmap for easy modification

crushtool --decompile crushmap.cm -o crushmap.txt

Modify the CRUSH map in the file crushmap.txt and change the lines with host to osd in the rules section.

# rules
rule replicated_rule {
        id 0
        type replicated
        step take default
        step chooseleaf firstn 0 type osd # <- change in this line
        step emit
}

# end crush map

Recompile crush map:

crushtool --compile crushmap.txt -o new_crushmap.cm

Update Ceph cluster with a new crush map:

ceph osd setcrushmap -i new_crushmap.cm

Check CEPH status via dashboard or via CLI

ceph -s

root@pve1:~# ceph -s
  cluster:
    id:     c638916b-9ad8-4739-bebe-c9037f31eb26
    health: HEALTH_OK

Ceph status become HEALTH_OK now

# Add Pool

Go to Datacenter | PVE Host | Ceph | Pools | Create

# Place VM on RBD Pool

When create a new VM, select RBD Pool that has been created

Good Luck 🙂

Source: https://www.redhat.com/en/blog/ceph-cluster-single-machine