FAQ
After VMs on a host are migrated to a destination host because of host failure, I shut down the VMs and the destination host.
Why does the state of the failed host frequently switch between normal and maintenance after it recovers?
This is a normal phenomenon for High Availability (HA). After the failed host recovers, it will synchronize VM information. However, the destination host has been shut down and the recovered host cannot confirm with the destination host whether the related VMs exist. As a result, the recovered host cannot complete VM synchronization, which causes frequent normal/maintenance state switches. In this case, start the destination host for the recovered host to complete VM synchronization.
Do I need to install a client for accessing the management platform?
No. To access CVM, enter http://CVM management IP address or https://CVM management IP address in the address bar of the Web browser. The following are CVM address examples:
• http:192.168.1.1
• https://192.168.1.1
• http://[172:20::2:31]
• https://[172:20::2:31]
Why do some management platform pages look different when they are accessed from different browsers?
This is because the browsers interpret some page elements differently. This issue is normal and does not affect the functionality of the product.
Why does the system prompt error 502 when I access the management platform?
The system will restart Tomcat during secure mode switching, stateful failover system setup, or patch upgrade and this will cause temporary access interruption. You can access the management platform correctly after a while.
What are the VM image file requirements for a VM migration?
To move a VM between hosts without moving its storage, make sure the following requirements are met:
• The VM image files are stored in a shared storage system.
• The source and destination hosts are both connected to the shared storage system.
To move a VM with its storage between hosts or move only the storage of a VM, make sure the following requirements are met:
• The available capacity of the source storage pool is greater than the capacity of the VM's storage volume. If the disk format changes after the migration, make sure the available capacity of the destination storage pool is at least twice the capacity of the VM's storage volume.
Are there any file system access requirements for VM backup?
Yes. The requirements vary depending on the backup method, as follows:
• To back up VMs to local storage, make sure the backup directory has been created and you have write access to that directory.
• To back up VMs to an FTP server, make sure the backup directory already exists on the server and your user account has permissions to create subdirectories and upload files.
• To back up VMs to an SSH server, make sure the backup directory already exists on the server and your user account has permissions to create subdirectories and upload files.
• For a successful backup, make sure no one deletes the backup directory during the backup. Backup anomaly occurs if the backup directory is deleted during the backup. For example, the backup data file might be put in the root directory if FTP is used.
What should I do when some incremental VM backup files are lost?
If an incremental backup file before a point in time is deleted or lost, you will be unable to restore the VM to that time point. To ensure a successful future VM restoration, select the VM in the navigation tree. In the backup management tab for the VM, perform a full backup before you continue with the incremental method of backup.
Why can't some guest OSs display all serial ports added on VMs?
This issue occurs because of the limitation intrinsic to the guest OS.
Is it normal that the management platform merges multi-level images of a VM after that VM is imported or restored?
Yes, it is normal that the management platform merges multi-level images of a VM after that VM is imported or restored.
How do I handle the volumes that have a suffix of _base_0 or _base_1 in the storage pool if no users are using them?
After the file merge, the management platform removes the VM from the user lists of the image files linked to the VM (image file with a suffix of _base_0 or _base_1 for example). If the user list of an image file is empty, no VMs are using that file. You can delete that image file to free up storage space.
How do I update the Virtio disk driver after I select a Virtio disk for a VM?
The update procedure depends on the guest OS. The following is the generic update methods for Windows 7:
• If you are using the Virtio disk as the system disk, add a floppy disk drive to the VM. Make sure you select a driver file that starts with virtio-win7 under the /vms/isos path when you add the floppy disk drive. Then, start the VM and install its guest OS. During the installation process, install the Red Hat VirtIO SCSI controller at prompt.
• If you are using the Virtio disk as a regular disk, add a floppy disk drive to the VM. Make sure you select a driver file that starts with virtio-win7 under the /vms/isos path when you add the floppy disk drive. After you add the floppy disk drive, start or restart the VM. Then, choose to install the hardware you manually selected from a list or location, and set the installation path to A:\win7\x86. To verify the installation, select Computer Management > Storage > Disk Management on the VM.
What requirements does the management platform have for the managed hosts?
The managed x86 hosts must use CPUs that support Intel-VT or AMD-V for virtualization. The managed ARM hosts must use ARM8.1 or higher CPUs and support VHE. Recommended hardware settings:
• CPU:
○ X86 hosts—CPUs supporting Intel-VT or AMD-V.
○ ARM hosts—CPUs supporting VHE.
• Memory:
○ X86 hosts—32 GB (minimum).
○ ARM hosts—16 GB (minimum).
• 300 GB HDD (minimum).