Containers

Alongside virtual machines, VM2Cloud VE runs containers. A container shares the node’s kernel rather than emulating a whole computer, so it starts in seconds and uses noticeably less memory — but it runs Linux only, and is less isolated than a virtual machine.

	Virtual machine	Container
Operating system	Any, including Windows	Linux only
Start-up	Seconds to minutes	Near-instant
Memory overhead	A full operating system	Very little
Isolation	Strong	Weaker — shares the node’s kernel
Best for	Anything you would run on a server	Many small Linux services on one node

Choosing between them

Use a container for lightweight Linux services where density matters. Use a virtual machine for anything running untrusted code, anything not Linux, and anything needing its own kernel.

1. Get a template

A container is created from a template, not from an ISO image.

1. Select a storage that accepts Container template content — local does by default.
2. Open its CT Templates panel.
3. Click Templates to browse the supplied list, select one, and download it.

You can also Upload a template you already have, fetch one with Download from URL, or Pull from OCI Registry to take a container image from a registry.

2. Create the container

Click Create CT in the header. The wizard has eight tabs.

General

Field	Notes
Node	Which server it runs on
CT ID	A unique number. The next free one is offered.
Hostname	The name the container knows itself by
Unprivileged container	Leave this ticked
Nesting	Only if this container will itself run containers
Add to HA	Protect it with high availability from the start
Resource Pool	Optional grouping
Password / SSH public key(s)	The root credentials. Load SSH Key File reads a key from a file.

Keep “Unprivileged container” ticked

An unprivileged container’s root user is not root on the node. A privileged one is much closer to it, and a container escape becomes a node compromise. Only clear this if something genuinely will not work without it, and understand what you are accepting.

Template

Select the storage and the template you downloaded.

Disks

Size the root filesystem and choose its storage. Containers usually need far less than a virtual machine — a few gigabytes is often plenty.

CPU and Memory

Set cores and memory. Both can be changed later, and unlike a virtual machine most changes do not need a restart.

Network

Choose the bridge or virtual network to attach to, and set addressing — DHCP, or a static address and gateway.

DNS

Leave on the host’s settings unless the container needs its own.

Confirm

Review, and create.

3. Start and use it

Select the container in the tree and click Start, then Console. Sign in as root with the password you set, or with the SSH key.

The container menu

Mostly the same as a virtual machine’s — see the guest menu reference — with these differences:

Entry	Notes
Resources	Memory, cores and root disk size, in place of Hardware
Network	Network adapters, as their own entry
DNS	Name resolution, as its own entry
No Cloud-Init	Initial settings are given in the wizard instead

Backups, snapshots, replication, the firewall, permissions and migration all work the same way as for virtual machines.

Backups and high availability

Containers are covered by backup jobs exactly like virtual machines, and can be added to high availability the same way. A backup job set to All or Exclude selected already includes them.

If something goes wrong

What you see	What to do
No template can be selected	None has been downloaded. Use CT Templates → Templates on a storage first.
The storage is not offered for the root disk	It does not have Container in its content types. See Storage management.
Something inside the container needs privileges it does not have	Expected in an unprivileged container. Consider a virtual machine rather than making it privileged.
A container inside this one will not start	Turn on Nesting.
It will not migrate	Containers are stopped for migration unless the storage is shared. Check where its root disk lives.

Still stuck? Contact VM2Cloud support.