ovftool VM export too slow even with jumbo frames enabled

[pardhivkarri]

Hi,

We need to decomm an old vSphere 5.5 environment. Trying to export VMs out of vCenter using OVFTool. The network speed is 10Gbps, dvs port and kernel adapter are set to MTU 9000.  Jumbo Frames are enabled all across , and firewall is wide open and tested it, but when we do an VM export using OVFTool it is only getting an average speed of 65Mbps and rarely topping to 103Mbps. Both the source (esxi host) and destination (centos7 physical server) are in the same datacenter. It looks like the source which is an ESXi 5.5 host is the bottle neck.

The VM is on SAN. For testing purposes we made sure there is only one VM on the host (the VM to be exported) and is powered off to make sure there is no load on the host.

Is there any fine tuning that we need to do on the ESXi host or vCenter or on the datastore end to make this transfer/export much faster as we need to do this for 100's of VMs which are larger than 100GB?

Running the below command from Centos 7 server,

ovftool --noSSLVerify vi://abcd:*******@vc.abc.com/DC1/vm/scvm /apps/vmstorage/

Thanks,

PK

[mhampto]

In my experience when issues with slow transfer speeds when Jumbo Frames is enabled, majority of the reason, somewhere in the topology is not configured correctly for Jumbo Frames.

Would you be able to turn off Jumbo Frames and see if connectivity end to end is re-configured for MTU of 1500?

What about the logs? Do we see anything on the logs on the ESXi host during when the OVFTool is running? What does the esxtop command look like from the disk and network perspective when the OVFTool is running?

There's also a possibility that there are disk latency on the datastore where the disk is residing. I recommend to run esxtop command on the ESXi host when the OVFTool is running. For more information, see Using esxtop to identify storage performance issues for ESX / ESXi (multiple versions) (1008205) | VMware KB .