Storage vMotion operation fails with the error: Insufficient disk space on datastore

Products

VMware vSphere ESXi

Issue/Introduction

Symptoms:

A Storage vMotion operation fails
The virtual machine is no longer running
When clicking on the Complete Migration option, you see the error:

Insufficient disk space on datastore 'Datastore_Name'.
The virtual machine configuration file (.vmx) contains entries similar to:

scsi0:0.present = "true"
scsi0:0.fileName = "/vmfs/volumes/datastore/VMname//XXX-scsi0:00_VMname.vmdk"
scsi0:1.present = "true"
scsi0:1.fileName = "/vmfs/volumes/datastore/VMname//XXX-scsi0:01_VMname_1.vmdk"
scsi0:0.DMotionParent = "/vmfs/volumes/datastore/VMname/VMname.vmdk"
scsi0:1.DMotionParent = "/vmfs/volumes/datastore/VMname/VMname_1.vmdk"
In the vmware.log file, you see entries similar to:

vcpu-2| [msg.hbacommon.outofspace] There is no more space for the redo log of /vmfs/volumes/datastore/VMname//xxx.vmdk. You
vcpu-2| may be able to continue this session by freeing disk space on
vcpu-2| the relevant partition, and clicking Retry. Otherwise,
vcpu-2| click Abort to terminate this session.
vcpu-2| ----------------------------------------
vcpu-2| Msg_Question: msg.hbacommon.outofspace reply=0
mks| MKS REMOTE failed to complete async op for authd connection!
vcpu-2| Msg_Question:

Environment

VMware ESXi 3.5.x Embedded
VMware ESX Server 3.5.x
VMware ESXi 3.5.x Installable
VMware ESX Server 3.0.x

Resolution

This issue occurs if the destination datastore does not have enough free space to accommodate the storage migration operation.

For the complete list of Storage vMotion requirements, see the Storage vMotion Requirements and Limitations.

To resolve this issue, you must ensure that you have an adequate amount of free space on the datastores. To free up space, consider:

Moving virtual machines or individual virtual disks to another Datastore to free space
Doing the Storage vMotion to different destinations, where each one has enough free space to allocate the migrated vDisks.
Removing old snapshots
Cleaning up VMware VMFS
Adding additional datastores
Increasing capacity

For more information about these operations, see Troubleshooting a datastore or VMFS volume that is full or near capacity (1003412).

You may have most of the options greyed out in the VMware Infrastructure (VI) Client. This occurs if the virtual machine is in the middle of a migration process. No changes are allowed until that migration task is completed. The Remove from Inventory and Add to Inventory options do not impact the status of the virtual machine.

To set the migration status of the virtual machine as completed:

Edit the .vmx file and comment out the Dmotion lines (using #).
Reload the virtual machine settings with the command:

In ESX:

# vmware-vim-cmd vmsvc/getallvms
# vmware-vim-cmd vmsvc/reload VMID_from_previous_command

In ESXi:

# vim-cmd vmsvc/getallvms
# vim-cmd vmsvc/reload VMID_from_previous_command

Note: Re-registering the virtual machine also has the same effect. For more information, see Registering or adding a virtual machine to the inventory (1006160) .
Retry the Storage vMotion operation after ensuring that the datastore has enough free space and that the migration status is completed.

Perform these operations to ensure a successful Storage vMotion:

Whenever possible, use an ESX/ESX 4.x host to perform the Storage vMotion process. The ESX host does not use snapshots for the task.
If the virtual machine is big, perform the Storage vMotion operation in multiple steps by moving one virtual disk at a time. To move one virtual disk at a time, start the Storage vMotion wizard, on the Select Datastore screen, click Advanced and move only one disk at a time.