VirtFusion

Resize a VirtFusion server: upgrade CPU, RAM and disk

Upgrade or downgrade a VirtFusion VPS by changing its package or resources, then grow the partition and filesystem inside the server so the new disk space is usable.

IntermediateVirtFusion VPS2 min read

To resize a VirtFusion server you change its package (or its individual resources) and then apply the change. CPU and memory take effect after a power cycle; extra disk space also needs the partition and filesystem grown inside the VPS.

Before you start

  • A backup of the server, especially before any disk change.
  • Free capacity on the hypervisor for the extra CPU, RAM and disk.
  • Admin access, or a WHMCS upgrade path set up for customers.

Warning: Shrinking a disk is not safe and is usually not supported. Downgrades should keep the same disk size or move the customer to a new server.

Resize the VirtFusion server

  1. In the admin area open Servers and select the server.
  2. Change the package to the larger plan, or edit CPU, memory and disk directly if you allow custom resources.
  3. Save. The new limits are stored on the server.
  4. Fully power off and start the server (a reboot from inside the OS may not apply new CPU and RAM).

If customers order upgrades in WHMCS, the VirtFusion module changes the package automatically when the upgrade invoice is paid.

Grow the disk inside the VPS

Many templates grow the root partition automatically on boot. If df -h still shows the old size, grow it manually. Example for a Linux VPS with an ext4 root on /dev/vda1:

growpart /dev/vda 1
resize2fs /dev/vda1

For XFS root filesystems (common on AlmaLinux and Rocky) use:

xfs_growfs /

Install cloud-guest-utils (Debian/Ubuntu) or cloud-utils-growpart (RHEL family) if growpart is missing.

Check afterwards

  • nproc shows the new core count and free -m the new memory.
  • lsblk shows the larger disk and df -h the larger filesystem.

Troubleshooting

  • Resources unchanged: the server was rebooted from inside instead of a full stop and start from the panel.
  • Resize refused: the hypervisor lacks free RAM or disk; migrate the server or free capacity.
  • Windows disk not larger: extend the volume in Disk Management after the resize.

Frequently asked questions

Is there downtime when resizing?

Yes, a short stop and start is needed for CPU and RAM changes.

Will a resize delete my data?

Growing a disk keeps data, but always back up first in case something fails.

Can customers resize themselves?

Usually through WHMCS upgrade orders, which call VirtFusion for them.

Next steps

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