For AI agents: the complete documentation index is available at https://docs.ovhcloud.com/en/llms.txt, the full documentation bundle is available at https://docs.ovhcloud.com/en/llms-full.txt, and this page is available as Markdown at https://docs.ovhcloud.com/en/guides/storage-and-backup/block-storage/cloud-disk-array/ceph-access-cluster.md.

How to Access a Cloud Disk Array Cluster from a Client Machine

View as Markdown

Connect a client to your OVHcloud Cloud Disk Array, add its IP to the ACL, install Ceph, configure ceph.conf, add the keyring and test

Objective

This guide shows how to configure a client (such as a Public Cloud instance or any server with a public IP) to connect to your OVHcloud Cloud Disk Array cluster using Ceph CLI tools.

Requirements

  • A Cloud Disk Array solution
  • The public IP address of the client machine you want to grant access to.
  • Access to the or to the
  • The Ceph monitor IPs, a Ceph user, and its secret key from the Control Panel. You can follow this guide to manage dedicated users.

Instructions

Step 1: Authorize Your Client's IP in the ACL

You must add your client machine's public IP address to the cluster's Access Control List (ACL) to allow it to connect. Follow this guide to add the IP in your Cloud Disk Array ACL.

Warning

Without this step, all connection attempts from your client will be blocked by the firewall.

Step 2: Install Ceph Common Packages

Make sure the ceph-common package is installed on your client machine.

On Debian/Ubuntu
On RHEL/CentOS Stream/Rocky Linux
sudo apt update
sudo apt install -y ceph-common

Step 3: Create the Ceph Configuration File

This configuration file tells your client how to reach the cluster’s monitors over the public network.

  1. Create the Ceph configuration directory:

    sudo mkdir -p /etc/ceph

  2. Create and edit the ceph.conf file:

    sudo nano /etc/ceph/ceph.conf

  3. Add a [global] section with your monitors’ public IPs, found on your Cloud Disk Array main Control Panel page.

    [global]
#Specific fsid           
fsid = aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee

#Force use secure protocol
ms_client_mode = secure

#Force the messenger v2 protocol
ms_bind_msgr2 = true

# Use the PUBLIC IPs provided for your Cloud Disk Array
mon_host =A.B.X.Y:6789,A.B.X.Y:6789,A.B.X.Y:6789

  4. Save and close the file.

Step 4: Create the Ceph Keyring File

Store the secret key in a keyring file to authenticate your user.

  1. Create the keyring file for your user:

    sudo nano /etc/ceph/ceph.client.[USERID].keyring

  2. Enter the key using the correct format:

    [client.[USERID]]
key = YOUR_SECRET_KEY_FOR_USER

  3. Restrict file permissions for security:

    sudo chmod 600 /etc/ceph/ceph.client.[USERID].keyring

Step 5: Test the Connection

Test your configuration, the ceph command will use the config file and keyring automatically.

# Check the overall health and status of the cluster
sudo ceph --id [USERID] status
 
# List the available storage pools in the cluster
sudo ceph --id [USERID] osd lspools

If these commands show cluster information, your client is successfully configured to access the Cloud Disk Array over the public internet.

Go further

Visit our dedicated Discord channel: https://discord.gg/ovhcloud. Ask questions, provide feedback and interact directly with the team that builds our Storage and Backup services.

For training or technical assistance implementing our solutions, contact your sales representative or visit our Professional Services page to request a quote and have your project analysed by our experts.

Join our community of users.

Was this page helpful?