VMs are not getting migrated from cluster to cluster

Products

• VMware vSphere ESXi

Issue/Introduction

VMware vMotion operations between clusters are consistently failing at exactly 20%.

You may also observe the following:

• vCenter reports the below failure message:
  

  “vMotion failed because the destination host did not receive data from the source on the vMotion network.”

 

• Using the ncat CLI command from the source ESXi host to the destination vMotion VMkernel IP on port 8000 fails:
  

  # nc -zv <destination_vmotion_vmk_ip> 8000 
    failed: Connection timed out

Environment

VMware vCenter Server 
VMware vSphere ESXi

Cause

• The inability to connect to the destination vMotion VMK IP on port 8000 is the reason for the vMotion failures.
• This may specifically be the result of one of the below:
  • Firewall rule somewhere in the datapath blocking port 8000.
  • Misconfiguration somewhere in the network underlay.
  • Physical connectivity issue. 

Resolution

• Look for firewall rules anywhere between the source and destination that could potentially be blocking connectivity on port 8000.
• Check for any misconfigured network devices.
• Check and confirm that the correct cables are used, that they are in good condition, and that they are securely plugged in.