Can I attach a single volume to multiple virtual machines?

NFS sharing can be used to share a single volume between multiple virtual machines.

A volume can only be attached to a single virtual machine at a time due to the lack of support for parallel access to a single disk by most operating systems and file systems.

However, NFS sharing can be used to share a single volume between multiple virtual machines.

Follow these steps:

1. Create a bootable volume with sufficient storage capacity for all your data.

2. Create a CPU-only virtual machine configuration from the volume in step 1 to serve as an NFS server.

3. Use a cloud-init script to install packages and enable NFS sharing.

   Example of an  NFS server cloud-init script:
   

   #cloud-config
   
   packages:
   - nfs-kernel-server
   package_update: true
   
   runcmd:
   - mkdir -p /data/nfshare
   - echo "/data/nfshare    *(rw,no_root_squash)" >> /etc/exports
   - exportfs -ravs

   Note: "/data/nfshare" and "*(rw,no_root_squash)" should be edited according to the required behavior.
   
   Example of an NFS client cloud-init script:
   

   #cloud-config
   
   packages:
       - nfs-common
   package_update: true
   
   mounts:
       - [ "10.0.0.128:/data/nfshare", "/mnt", "nfs", "defaults", "0","0" ]
   
   runcmd:
       - mount /mnt  

   Note: "10.0.0.128:/data/nfshare" and "/mnt" must be changed according to the required behavior.

4. Create a security rule to permit traffic to port 2049/TCP on your local subnet (eg: 10.1.1.0/24).

5. Create one or more VMs with your desired configurations and attach the cloud-init NFS clients example script.

6. Optionally, the client configurations can be saved as a Provisioning Profile for future usage.

References:

• Infrahub Docs | Storage Types
• Infrahub Docs | Provisioning Profiles
• Infrahub Docs | Volume Attachment
• Configure NFS Server on Ubuntu - Debian
• Configure NFS Client on Ubuntu - Linux
• Cloud config script examples