After a host power failure, vMotion fails with the error: Module is not loaded

This issue occurs because the vMotion module fails to load automatically after a power failure. To resolve this issue, you must re-enable vMotion after the host power failure.
To re-enable vMotion:
Click the host in vCenter Server and then click the Configuration tab.
Click Properties on the vSwitch where the vMotion VMkernel port group is located.
Click the vMotion port group and click Edit.
Deselect the vMotion Enabled option.
Click OK and then click Close.
Connect to the host using SSH.
Run this command to verify if the vMotion module is loaded:
vmkload_mod -l | grep migrate
If the above command does not return any values, run this command to load the module:
vmkload_mod migrate
Run this command and verify if the vMotion module is now loaded:
vmkload_mod -l | grep migrate
Run this command to restart services:
services.sh restart
Repeat Steps 1 to 3 and select the vMotion Enabled option. This enables vMotion.
Migrate virtual machines to another host.
Reboot the host.
Run this command to verify if the vMotion module loads properly:
vmkload_mod -l | grep migrate
You must see an output similar to:
# vmkload_mod -l | grep migrate
migrate                  2    252
For more info read the following article from VMware