vMotion failure

[Moudy_87]

Hey guys, bit of a tricky one. I have configured vMotion on the managment vmKernel configured IPs correctly set the MTU jumbo frames acroos 9000. When I try to migrate machine while they powered on I get various errors this one of them;

Failed to migrate the virtual machine for reasons described in the event message

Possible Causes:

• The virtual machine did not migrate. This condition can occur if vMotion IPs are not configured, the source and destination hosts are not accessible, and so on. Action: Check the reason in the event message to find the cause of the failure. Ensure that the vMotion IPs are configured on source and destination hosts, the hosts are accessible, and so on.

The 2 hosts can communicate with each other, the datastore is mounted and shared between the 2 hosts, I can ping each host from the other one. I also could vmkping each host no issues.

What I see strange and driving me crazy is, if I power off the VM and start the same migration (Same source same destination as previous) it migrates fine no worries. I cannot figure out why the hot migration doesn't work but cold migration works fine?

Any tips on where to look and how to reslove this issue will be very thankful.

[daphnissov]

Set your MTU back to 1500 and try again. You may have a jumbo frames issue across the switch(es) where that traffic passes.

[Moudy_87 · Accepted solution]

This is a home lab and I only have 1 switch between the 2 hosts. It was set to 1500 first and was failing, but your comment made me remember that I have added the switch very recently and forgot to enable the jumbo frames on. I enabled it few hours ago and done few hot migration perfectly fine without any problems. Thanks