In this article, you will learn:

• How to prepare the VM to change parameters
• How to change CPU or RAM
• How to change disk size
• Common issues
• Frequently asked questions

Make changes to the virtual machine parameters in the OpenNebula SunStone interface.

First, select the virtual machine by following these steps:

1. Log into the ON SunStone interface.
2. In the left menu, select Instances VMs.
3. Choose the VM to change the parameters.

Before changing the parameters, make sure the machine is in the POWEROFF state:

You can increase and decrease both CPU and RAM values. Follow these steps:

1. In the VM detail, select the Capacity tab.
2. Click the Resize button.
3. Set the required values
4. Confirm with the Resize button.

You can only increase disk space, not decrease it. If you need to reduce the disk size of the virtual machine, create a new VM and migrate the data to it.

Increase disk space by following these steps:

1. In the VM detail, select the Storage tab.
2. Click the Resize icon next to the disk you want to indrease.
3. Set the desired value in the pop-up window.
4. Confirm with the Resize button.

If the increase is successful, you will see the new value in the Size column for the corresponding Image. This change should go through the DISK_RESIZE state back to POWEROFF. If the size returns to its original value, contact support. Report the name of the Cloud service and the specific VM.

After increasing the disk and booting up the VM, check the filesystem. In Linux, use the command df -h to do this. If the filesystem didn’t change, Power Off (hard) and turn the VM on again. Restarting is not enough.

Common problems with changing cloud VM parameters include:

• Inactive Resize button
• Error decreasing disk size
• Error with CPU/RAM quota
• Failed to increase parameters

Issue: The Resize button is not active when changing CPU/RAM.

Cause: The virtual machine is probably not powered off.

Solution: Shut down the virtual machine and make sure it is in the POWEROFF state.

Issue: There is an error: [one.vm.diskresize] New disk size has to be greater than current one.

Cause: You can only increase the disk size, not decrease it.

Solution: Create a new virtual machine with the required parameters.

Issue: There is an error: [one.vm.resize] User [****] : group [****] limit of X reached for MEMORY/CPU quota in VM.

Solution: Free up memory or CPU by either throttling/killing other VMs or upgrading the service.

Issue: There is an error: Parameter increase failed.

Solution: Undeploy (hard), then Deploy and try increasing the parameters again.

Question: Can I change VPS ON parameters this way?
Answer: No, follow this guide for the VPS ON service.