The 'vMotion failed at 10%. Insufficient network bandwidth' error indicates limited network resources during vMotion. Troubleshoot by checking for network congestion, MTU settings, and connectivity between hosts. Verify proper host configuration, port group settings, and resource contention. Restart management agents if needed.
Or take a look on one of this:
Network Congestion: Even if your network appears fine, temporary spikes in network traffic or congestion during the vMotion process could cause the error. Check for any other heavy network activity or bandwidth-intensive tasks on the involved hosts or network segments.
MTU Settings: The Maximum Transmission Unit (MTU) size must be consistent across all networking components involved in the vMotion process. Ensure that the MTU size is large enough to accommodate vMotion packets without fragmentation.
Connectivity Issues: Verify that there are no connectivity problems between the source and destination hosts. Ensure you can successfully ping each host from the other, and validate DNS resolution for both hosts.
Network Configuration: Double-check the network settings on both ESXi hosts participating in the vMotion. Confirm that they are on the same subnet, and they can communicate with each other.
Port Group Settings: Ensure that the VMkernel port for vMotion is correctly associated with the appropriate distributed or standard port group, and it has the necessary permissions.
Resource Contention: Inspect the resource utilization on both the source and destination hosts, including CPU, memory, and storage. If either host is experiencing high contention, it could lead to vMotion failure.
Restart Management Agents: If all else seems normal and the issue persists, consider restarting the management agents on both ESXi hosts using the vSphere client or SSH.
vMotion Network: If you have a dedicated vMotion network, verify that it is functioning correctly and that it is not shared with other traffic to avoid contention.
By carefully reviewing these aspects and addressing any issues found, you can troubleshoot and resolve the 'Insufficient network bandwidth' error during vMotion migration in your VMware environment. Remember to document any changes made during troubleshooting for future reference.
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