We recently deployed 5-6 new hosts in one of our production Vmware ESXi clusters in order to migrate VMs off older hosts and upgrade them. If you are attempting a vMotion migration between two ESX/ESXi hosts, and the vMotion task reaches 14%, then times out with this error message:

The vMotion migrations failed because the ESX hosts were not able to connect over the vMotion network. Check the vMotion network settings and physical network configuration.
vMotion migration [-1407923943:1396365628089329] failed to create a connection with remote host <ip-address>: The ESX hosts failed to connect over the VMotion network
Migration [-1407923943:1396365628089329] failed to connect to remote host <ip-address> from host <ip-address>: Timeout
The vMotion failed because the destination host did not receive data from the source host on the vMotion network. Please check your vMotion network settings and physical network configuration and ensure they are correct.

ESXi Recent Tasks list shows vmotion task stuck at 14%
vMotion migration failed error

You want to make sure your vmotion network is setup properly, vmotion is enabled on the vswitch and follow steps in this kb article. We verified that the configuration was correct but still could not vmotion VMs from old hosts to new ones.

If you’ve tried everything and still cannot get the vmotion to work, try deleting the vswitch completely and add it back to the host. If you are using host profiles to apply these changes on multiple esxi hosts then make sure you only enable network settings pertaining to vmotion vswitch and then try vmotion. Deleting and recreating the vswitch should fix the issue as it did for us.