Phase 4 — Daily administration#

11 lessons · Level: intermediate

This phase is the daily work: templates, packages, users, servers, migration, and backups.

What is in this phase#

Lesson 1 — OS templates and media#

In plain words#

A template is a prepared OS image. When the customer chooses "Ubuntu 24.04", VirtFusion copies that template. Then cloud-init writes the hostname, the IP, the password, and the SSH key into it.

Templates are managed at Media → Templates. You can arrange them in groups, such as Linux, Windows, and Panels.

What to remember#

Custom ISO files#

A customer can install from their own ISO. VirtFusion streams the ISO from a remote server, and you give only the URL of the ISO. Host a large ISO in advance.

Your own icons#

You can add up to 20 of your own icons, or logos. Keep them in /opt/virtfusion/app/control/public/img/logo. This helps if you have an OS image with your own brand.

Windows templates#

Windows needs separate attention:

• The VirtIO drivers must already be in the template.
• Cloudbase-Init, which is cloud-init for Windows, must be installed.
• Performance is much better with Hyper-V enlightenments turned on.

The Cloudbase-Init log is at C:\Program Files\Cloudbase Solutions\Cloudbase-Init\log\cloudbase-init.

Lesson 2 — Packages (the resource plans)#

In plain words#

A package is your sales plan: the vCPU, the RAM, the disk, and the traffic. A server is always made from a package.

Go to Admin → Packages → Create.

What a package holds#

Practical advice#

• Put the resources in the package name, such as VPS-2C-4G-80N. It is then

easy to match in the billing system.

• The billing module needs the package ID, not the name. Write the ID

down.

• Control oversell with the CPU throttle. One customer then cannot take the

whole node.

Lesson 3 — Make a user, and extRelationId#

In plain words#

Each customer gets one VirtFusion user. The billing system, or your own application, makes this user and puts its own id into the extRelationId.

users.id in your application = 4821
        │
        ▼
VirtFusion user (extRelationId = 4821, its own id = 93)

To find that user later, your own id is enough:

GET /api/v1/users/4821/byExtRelation

The rules#

1. One VirtFusion user for each customer, and no more.
2. Set the extRelationId once, then do not change it.
3. If you make a user by hand, do not forget the extRelationId. Without it

the SSO login fails.

CAUTION: In the WHMCS module, the error "Oops! Something went wrong" usually has three causes. One, HTTPS is not correct. Two, a customer login was attempted with a VirtFusion administrator account. Three, a user made by hand has no extRelationId mapping.

Lesson 4 — Make a server, and build it#

The two steps#

A server is made in two steps. If you do not know this, the API is confusing.

In the panel the two steps look like one. In the API they are separate calls: POST /servers, and then POST /servers/{id}/build. Phase 5 gives the detail.

What you give at build time#

• The OS template
• The hostname
• The root password, or the SSH key of the customer
• A provisioner script, if you want one

Provisioners#

A provisioner is a script that runs at the first boot. It can be bash, python, PowerShell, or cloud-init YAML.

1. Make the script at Server → Provisioners.
2. Attach it to a template at Media → Templates.
3. A server built from that template runs the script by itself.

The server variables, such as the hostname and the IP, can be injected into the script.

Provisioners are useful to install a firewall, add a monitoring agent, set your own SSH banner, or install a panel.

To debug: if the script fails, look inside the server at /var/log/cloud-init.log and /var/log/cloud-init-output.log.

Lesson 5 — The daily server tasks#

The task list#

Stop an accidental delete#

Turn "do not disturb" on for an important server:

vfcli-ctrl server:dnd enable SERVER_ID
vfcli-ctrl server:dnd disable SERVER_ID

See the last password#

vfcli-ctrl server:password show SERVER_ID

Reset the traffic count#

vfcli-ctrl server:traffic-statistics reset-all
vfcli-ctrl server:traffic-statistics reset-all --include-datastore

CAUTION: Do not use --include-datastore unless you must. It also deletes the old traffic history. You then have no evidence in a billing dispute.

Lesson 6 — Migration: hybrid and live#

The two kinds#

The conditions for a live migration#

• The server is online, suspended, or awaiting setup. If it is offline, use

--force-offline.

• SSH for root is on at the destination node, on the correct port.
• Every IP of the server is valid at the destination node. If not, the network

dies.

• The storage mount points exist at the destination, and all storage runs.
• The CPUs of the source and the destination are from the same vendor.

The documentation advises this: keep the two hypervisors as identical as you can, the OS version and the libvirt and QEMU versions included.

CAUTION: A server with a NAT interface still goes through no migration of either kind. Nor does a server that holds an asset such as a GPU.

A hybrid migration that is stuck#

Go to Server → Migrations. Open the log of the stuck migration. Copy the first command in the Commands part, and run it over SSH on the control server.

Lesson 7 — Elevate: a test without the risk#

In plain words#

Elevate, from version 4.1, lets you make temporary changes to a server. Later you either commit them or discard them.

1. Choose the drive to elevate.
2. Make the changes on the server, and test them.
3. If the result is good, commit each drive. If it is not, discard. The server

returns to its condition at the moment of the elevate.

Elevate is useful for a large upgrade, a kernel change, or a risky configuration test. It is the nearest thing to a Proxmox snapshot.

Lesson 8 — Backup Manager (v7)#

In plain words#

Version 7.x brought a completely new backup system. It is incremental and encrypted, and it has more than one storage backend.

The backup kinds#

The system manages the chain itself. After a set interval, 7 days by default, it starts a new chain.

The storage backends#

• SSH and SFTP
• S3-compatible (AWS, MinIO, Wasabi, Cloudflare R2, Backblaze B2)
• Proxmox Backup Server (PBS), with deduplication at chunk level
• FTP and FTPS
• Rclone

The setup#

1. Backup Manager → Storage — give the connection details of the backend.
2. Schedule — join the storage to a hypervisor, and set the interval.
3. The first backup is always full. After that it runs at the set interval.

Retention#

You can join "Keep Last N" to either policy. The last N backups then stay, whatever their age.

Restore#

From the administrator interface you choose the disk, the chain, and the restore point. You can also restore to another server, which is called a cross-server restore.

Note: The target server stops during a restore. When the work is finished, it does not start by itself. This is deliberate, so that you can correct the configuration before it starts.

Lesson 9 — User backups and disaster recovery#

Backups at user level#

A customer can take their own backups, on demand or at a set time.

The setup has three steps:

1. Backups → Backup Storage — add the storage, and choose the hypervisor

that uses it.

1. On the remote backup server: make a Unix user, put the public SSH key of

VirtFusion into authorized_keys, and install rsync.

1. Backups → Server Backup Plan — make the plan, and give it to a package

or to a named server.

The customer then sees the options in the "Backups" tab of their server.

The error "Failed to login on the SSH2 check" means a connection or firewall problem between the control server, the hypervisor, and the backup server.

Disaster recovery (at hypervisor level)#

vfcli-hv dr exists so that you can recover when a whole node fails.

vfcli-hv dr:backup                          # everything
vfcli-hv dr:backup --only-servers=1754,1253 # named servers
vfcli-hv dr:backup --exclude-system-data    # the server disks only

• The storage is S3-compatible, or a local partition.
• For S3, install the AWS CLI and keep a profile named virtfusion in

/root/.aws/config.

• The configuration file is /home/vf-data/conf/dr.json, for compression and

retention.

• Run it regularly with cron.

To replace a node, do these four steps:

1. Install VirtFusion on the new hardware.
2. Give it access to the backup.
3. Attach it to the control server.
4. Restore the system files and the servers.

Limit: DR takes the local disks only. Shared storage such as Ceph is left out.

The backup of the control server#

This is the part that gets the least attention. Without a backup of the database and the encryption key of the control server, you cannot recover the panel, even when every hypervisor is alive.

The "System Backup" guide of VirtFusion shows this process. Run it regularly, and keep the result on another machine.

Lesson 10 — Import an old KVM server#

In plain words#

You can bring a VM into VirtFusion from another panel, such as SolusVM or Virtualizor. But you do the whole task by hand. There is no automatic import tool.

The steps#

1. Stop the server. Every disk operation must happen offline.
2. Prepare the disk. For LVM, convert it to an image with qemu-img.

VirtFusion uses qcow2 by default, and raw also works.

1. Install cloud-init and the QEMU guest agent inside it. Without them

VirtFusion cannot fully control the server.

1. Clean the network configuration. On Debian, keep only

source /etc/network/interfaces.d/* in /etc/network/interfaces, so that cloud-init can take control.

1. Make a server of the same size in VirtFusion, and install a similar OS.
2. Move the prepared disk to the hypervisor, with the correct name:

[UUID]_[DISK_ID].img.

Lesson 11 — Mailouts, localization, and traffic#

Mailouts#

Use Mailouts to send a maintenance notice or an announcement to every customer. To tell people before a node reboot or network work is professional.

Localization#

The panel can appear in more than one language. If you have customers who speak Bangla, look at the language list.

Traffic accounting#

• The monthly bandwidth is counted for each server.
• You can set a limit in the package. Decide the policy for a server that

passes the limit: reduce its speed, or suspend it.

• If you change the creation date of a server, its monthly history is

deleted:

  vfcli-ctrl server:creation-date SERVER_ID '2026-08-01 00:00:00'

At the end of phase 4 you can#

• Manage templates and ISO files, and prepare a Windows template
• Make a package you can sell
• Keep the customer user and the extRelationId mapping correct
• Make a server, build it, and run a provisioner
• Use migration and Elevate
• Arrange backups, user backups, and disaster recovery
• Import an old KVM server

Next: Phase 5 — API and integration