On performing a Storage vMotion task to move a VM to another datastore, the following error message was received:
A general system error occurred: The migration has exceeded the maximum switchover time of 100 second(s). ESX has preemptively failed the migration to allow the virtual machine to continue running on the source. To avoid this failure, either increase the maximum allowable switchover time or wait until the virtual machine is performing a less intensive workload.
In order to resolve this issue, the VM was required to be powered off, and the fsr.maxSwitchoverSeconds was required to be modified, in this instance to 150 seconds. This can be performed as below:
1) Highlight the VM and select ‘Edit Settings.
2) Select ‘Options’.
3) Select ‘Advanced > General’.
4) Select ‘Configuration Parameters.
5) Select ‘Add Row’.
6) Input the Name ”fsr.maxSwitchoverSeconds’ and the new value in seconds.
7) Apply the changes and power on the VM.
The symptom as described in http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1010045, is caused by:
A virtual machine with many virtual disks might be unable to complete a migration with Storage vMotion. The Storage vMotion process requires time to open, close, and process disks during the final copy phase. Storage vMotion migration of virtual machines with many disks might timeout because of this per-disk overhead.
This timeout occurs when the maximum amount of time for switchover to the destination is exceeded. This may occur if there are a large number of provisioning, migration, or power operations occurring on the same datastore as the Storage vMotion. The virtual machine’s disk files are reopened during this time, so disk performance issues or large numbers of disks may lead to timeouts.
The default timeout is 100 seconds, and can be modified by changing thefsr.maxSwitchoverSecondsoption in the virtual machine configuration to a larger value.
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