Disks
Disks provide persistent block storage for your VMs. All disks use SSD-backed storage to ensure high performance and reliability. Disks are independent resources that can be created, attached, detached, and moved between VMs, allowing you to preserve data beyond the lifecycle of any individual VM.
How disks work
Each VM requires at least one boot disk containing the operating system. You can also attach up to 9 additional data disks to a VM for extra storage. Disks can be up to 4 TB in size.
Disks persist independently from VMs—if you delete a VM, attached data disks remain available and can be attached to a different VM. This allows you to separate compute and storage lifecycle management.
All disks use the persistent storage class, which ensures data survives hardware failures and can be safely detached and reused.
Zonal scope
Disks are zonal resources—each disk exists in a specific availability zone. When you create a disk, you must specify which zone it should be created in.
A disk can only be attached to a VM in the same zone. If you need to move data between zones, you must copy the data to a new disk in the target zone.
Boot disks
Each VM requires exactly one boot disk containing the operating system. Boot disks are configured with a disk image provided by evroc that defines the VM's OS. If you don't specify a boot disk size, the default size for the selected image is used (typically 50 GB). Boot disks can be up to 4 TB.
Available disk images
The available disk images are:
| Profile Name | Version | CLI image name | Default size |
|---|---|---|---|
| Minimal Ubuntu | 24.04 | ubuntu-minimal.24-04.1 | 5 GB |
| Ubuntu | 24.04 | ubuntu.24-04.1 | 50 GB |
| Ubuntu | 22.04 | ubuntu.22-04.1 | 50 GB |
| Rocky Linux | 10.0 | rocky.10-0.1 | 50 GB |
| Rocky Linux | 9.6 | rocky.9-6.1 | 50 GB |
| Rocky Linux | 9.5 | rocky.9-5.1 | 50 GB |
| Rocky Linux | 8.10 | rocky.8-10.1 | 50 GB |
| openSUSE | 15.6 | opensuse.15-6.1 | 50 GB |
| openSUSE | 15.5 | opensuse.15-5.1 | 50 GB |
| SLES | 15.6 | sles.15-6.1 | 50 GB |
| SLES | 15.5 | sles.15-5.1 | 50 GB |
| SL Micro | 6.1 | sl-micro.6-1.1 | 50 GB |
Use the CLI image name with the --image flag when creating a boot disk:
evroc compute disk create mybootdisk --zone=a --image=ubuntu.24-04.1
Note: GPU VMs only support Ubuntu 24.04.
Data disks
VMs can have up to 9 additional data disks for storage beyond the boot disk. Each data disk:
- Can be up to 4 TB in size
- Is created unformatted and must be formatted by you before use
- Can be attached and detached from VMs independently
- Persists when the VM is deleted.
- Appears as a block device (e.g.,
/dev/vdb,/dev/vdc) in the VM's operating system
Hotswap disk attachments
You can dynamically attach and detach disks from running VMs using Hotswap Disk Attachments.
Next steps
- Learn about Regions and zones and how disks relate to zones
- Learn how to create and attach additional disks
- Learn about Hotswap Disk Attachments for attaching disks to running VMs
- See the Functional Description for more details on VM storage