Migration [xxxx:xxxx] failed to connect to remote host <x.x.x.x> from host <y.y.y.y>: Network unreachable.
Usually this is a pretty straightforward fix: correct whatever network issue is preventing communication between the vmkernel ports. However, I recently encountered an issue where the network was configured properly, traffic was flowing, and vMotion still failed.
Everything with the multi-NIC vMotion config checked out:
- Two separate VMkernel ports on the relevant vSwitch with IPs on the same subnet.
- One vmnic active and one standby for each VMkernel port.
- Active/standby adapters on the second VMkernel port were the inverse of the first.
- vMotion enabled on the vMotion VMkernel ports.
- 9000 MTU on each vSwitch and VMkernel port
- 9000 MTU on the relevant switch and switchports.
- Relevant switchports tagged for the appropriate VLAN.
(The configuration is pretty straightforward, as outlined in the VMware KB: kb.vmware.com/kb/2007467)