Problems running VMWare Converter to perform V2V       'An error occurred while opening a virtual disk.'

Posted on 2014-11-26
Last Modified: 2014-11-27
Dear all,

I'm trying to use VMWare Converter Standalone to perform a V2V migration from one DC to another.

Plan is to perform the initial sync, and then sync changes at the point of cut over.

As a test, I am trying to replicate one server.

I receive the following error;   An error occurred while opening a virtual disk. Verify that the Converter server and the running source machines have a network access to the source and destination ESX/ESXi hosts.

I have turned SSL off changed to 'false' in the Worker.xml and restarted the VMWare Converter Worker service, I receive the same error.

The source and target are crossing multiple firewalls, however there is no NAT and I can test connectivity to the target from source server by telnetting on 443 and 902 in order to confirm the ports are open.

Any suggestions or ideas would be appreciated!
Question by:drm256
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Expert Comment

ID: 40467318
I have got around this in the past by doing a P2V. Basically in VMWare converter just enter the IP of the machine to migrate and let it install the client and convert it to your destination. Just be sure to stop any services to stop clients connecting like SQL etc.

Its not pretty but its worked without fail for me in the past.

Author Comment

ID: 40467361
Unfortunately I need to sync in advance and then the updates as I have multiple servers to cut across at once. I won't get a outage window big enough to move from scratch.
LVL 121
ID: 40467436
Are you doing it as per my EE Article

HOW TO:  Synchronize changes when completing a P2V or V2V with VMware vCenter Converter Standalone 5.1

Let me know, and we can see if we can work this out....
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Author Comment

ID: 40467500
Hi Andrew - yes, although I'm not doing it myself, that is what is being followed.
LVL 121
ID: 40467538
Have you installed VMware Converter on the Server to be converted?

What is the OS ?

Are you using Dynamic Disks ?

Author Comment

ID: 40467554
Converter is installed on the server to be migrated.

It's win 2008.

Dynamic disks - I'll have to check that with the admin....

Author Comment

ID: 40468475
Checking the source servers, all the disks are configured as Basic disks.
LVL 121
ID: 40468505
at what stage do you get the error message ?

e.g. percentage of the conversion ?

Author Comment

ID: 40468582
The actual conversion doesn't start or make any progress.

When we click finish (to start the conversion) - the error is displayed.
LVL 121
ID: 40468618
Did you accept the ESXi host SSL security footprint, when adding ESXi to vCenter Server ?

Author Comment

ID: 40468624
I've asked the guys to check this.  Do they just remove it from vcentre and add it again? No issues/ impact etc?
I disabled SSL in the worker.xml file I was hoping this might of worked around this, if they haven't accepted the thumbprint when originally adding the host?

To be clear - is this prompt when they first built the ESX hosts and added to vcentre (months and months ago)?
LVL 121
ID: 40468680
No impact to VMs.

To be clear - is this prompt when they first built the ESX hosts and added to vcentre (months and months ago)?


Author Comment

ID: 40468779
I've asked whether it's possible to remove and readd the ESX host to vcentre.

The environment is hosting live VM's which I cannot take down.

The admin guys are talking about needing to put the host into maintenance mode, move the VM's to different hosts within the cluster. Remove the host from the cluster etc......   This seems to have risk and impact to the VM's. Is this necessary / correct?
LVL 121

Accepted Solution

Andrew Hancock (VMware vExpert / EE MVE^2) earned 500 total points
ID: 40468791
If you have a Cluster, adding a remove Hosts, does cause complications.

Did they response with whether they had accepted the SSL thumbprint?

there is an option, available (maybe) sometimes, in Administration, vCenter Server Settings > SSL

Also check DNS resolution, e.g. can hosts and vcenter be resolved correctly.

Author Comment

ID: 40468953
Issue appears to have been DNS related.

I added host entries for the target ESX hosts, and the sync is now running.

Thank you!

Author Closing Comment

ID: 40468957
The ESX host must reply back during initial setup with it's full DNS name.
The source VM's were not able to resolve that name / domain.
Adding this to the source VM's host file has resolved this.

Thanks again!

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