While attempting to back up VMware sources, users may encounter a specific error message: "Can't disable vMotion because it is already disabled. You must re-enable it if no vMotion or backup are running"
This issue can disrupt backup operations and is associated with the VMware VDDK VixDiskLib_PrepareForAccess function.
This article is for Zmanda Enterprise version 5.1
Preventing the Issue:
To prevent this issue, consider the following measures before initiating backups:
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VM Exclusivity: During backup jobs, set the Virtual Machine (VM) to be Excluded from vMotion.
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Backup Windows: Minimize vMotion activities during backups to prevent conflicts.
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Scheduling: Schedule backup jobs during periods of lower activity when vMotion is less likely to occur.
Issue:
A VDDK error occurs during virtual disk reading due to a configuration conflict with the VMware VDDK library (VixDiskLib_PrepareForAccess function).
This function is designed to prepare virtual disks for access, and within this process, it attempts to temporarily disable storage vMotion for the virtual machine before initiating the backup. However, the error signifies that storage vMotion is already disabled at the vCenter level, preventing the VDDK from modifying this setting and leading to the reported error. This issue is specific to certain environments and VDDK library configurations.
Solution:
Follow these steps to fix the issue.
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Database Modification: Make changes to the VMware vCenter database to clear the flag related to vMotion.
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VM Re-Addition: Alternatively, re-add the VM to the vCenter inventory.
For detailed guidance on resolving this issue, refer to the solutions provided in the VMware article linked: VMware Knowledge Base