Concepts — Virtual machines
Architecture
A Hikube VM instance combines a compute template (vCPU and RAM), one or more disks, a network configuration and, optionally, GPUs. You manage them from the console.
Terminology
| Term | Description |
|---|---|
| Project | Isolated space that groups your resources and carries quotas (CPU, Memory, Storage). Formerly called tenant. |
| VM instance | Virtual machine. Its name (3 to 16 characters, lowercase letters, digits and hyphens, starting with a letter) cannot be changed after creation. |
| Instance type | CPU/RAM template, defined by a series (S, U, M) and a size (for example u1.xlarge). |
| System image | Operating system installed on the system disk (Ubuntu, Debian, Rocky Linux, Windows Server…). |
| System disk | First disk of the VM, the one it boots from. By default it is named after the VM. |
| Data disk | Additional disk, empty at creation. It appears in the OS as an additional block device (/dev/vdb, /dev/vdc…). |
| Replication | How a disk's data is copied across several nodes: Asynchronous or Synchronous. |
| Firewall | Filtering of inbound traffic on the public IP: only the allowed ports are open. |
| VPC | Private network of the project, divided into subnets, to which a VM can be connected. See Networking. |
| cloud-init (User Data) | Initialization script run when the VM boots (packages, users, commands). Not available for Windows. |
Instance types
| Series | Label in the console | vCPU:RAM ratio | Sizes |
|---|---|---|---|
s1 | Standard (S) | 1:2 | small (1 vCPU) to 8xlarge (64 vCPU) |
u1 | Universal (U) | 1:4 | medium (1 vCPU) to 8xlarge (32 vCPU) |
m1 | Memory (M) | 1:8 | large (2 vCPU) to 8xlarge (32 vCPU) |
The full list of sizes is in the overview.
Storage
Each disk created with the VM is configured in the Storage step of the wizard:
| Parameter | Values | Notes |
|---|---|---|
| Volume Name | Generated from the VM name (ma-vm, ma-vm-2…) | Editable |
| Size (GB) | 20 GB minimum, 4096 GB maximum | System disk: 40 GB minimum for Oracle Linux, 28 GB for Windows Server; the console raises the size to that minimum when you pick the image |
| Replication Type | Asynchronous Replication (Recommended) or Synchronous Replication | See below |
| Disk Encryption | Enabled / disabled | LUKS encryption of data at rest |
| Mode | RTO | RPO | Use |
|---|---|---|---|
| Asynchronous Replication | < 5 min | < 5 min | Default choice, suitable for most uses |
| Synchronous Replication | < 5 min | < 1 min | Data for which the maximum tolerated loss must be minimal |
A disk can also be Existing: it is then chosen among the project's disks that are not attached to any VM. The system disk can only be a disk containing an image; data disks can only be disks without an image.
Disks are resources in their own right, managed in the Disks menu: see Disks.
Network
| Wizard option | Default | Effect |
|---|---|---|
| Public IPv4 Address | Enabled | The VM gets a public IP reachable from the Internet. |
| Enable Firewall | Enabled | Only the Allowed Ports are open for inbound traffic (SSH 22 checked by default; HTTP 80, HTTPS 443 and custom ports optionally). |
| Firewall disabled | — | All ports of the public IP are open. In that case, protect the VM with a firewall in the OS. |
| VPC Networks (Secondary) | None | Each selected subnet adds a private network interface to the VM. |
Lifecycle
Statuses shown in the console: Creating, Running, Starting, Stopping, Stopped, Restarting, Deleting, Error, Failed, Unknown.
The Automatic Restart option (Configuration step of the wizard, or Advanced Configuration when editing) makes the VM restart automatically after an unexpected crash. It is disabled by default.
What can be changed after creation
| Item | Editable | Effect |
|---|---|---|
| Name, system image, system disk | No | To change the system disk, delete the VM and recreate it from the disk you want (Existing option) |
| Instance type | Yes | Applied on the next VM restart |
| Data disks (add, detach) | Yes | Applied on the next VM restart; a detached disk stays in Disks with its data |
| GPU | Yes | Applied on the next VM restart |
| Public IP, firewall, ports, VPC | Yes | Applied without restart |
| SSH keys | Yes | Offer to reload the user-data, applied at the next restart |
| cloud-init script, automatic restart | Yes | Script replayed after Reload UserData and a restart |
After you save a change of instance type, disks or GPUs, the console shows Restart required: restart the VM to apply it.
Quotas
Each project has CPU, Memory and Storage quotas. The wizard shows the current usage, the planned addition and the total; the Next button stays disabled as long as the new VM exceeds a quota. The same check applies to the Save button when editing.
The wizard also shows an estimate of the VM cost: instance type, new disks, GPUs, Windows license if applicable, and public IP.