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VMware VMX Protocol Error - Connect IT Community | Kaseya
<main> <article class="userContent"> <h2 data-id="summary"><strong>SUMMARY</strong></h2> <p>Virtual machine backups fail on the Unitrends appliance and on VMware</p> <h2 data-id="issue"><strong>ISSUE</strong></h2> <p></p> <h3 data-id="purpose">Purpose</h3> <p>To explain the error message “Fault string: A general system error occurred: Protocol error from VMX.”</p> <h3 data-id="applies-to">Applies To</h3> <p>VMware Virtual Clients and Unitrends Backups Appliance 6.x</p> <h3 data-id="symptoms">Symptoms</h3> <p>Virtual machine backups fail on the Unitrends appliance and on VMware.</p> <ul><li>Snapshot of a Windows server that has the Quiesced Guest file system option enabled fails</li> <li>Cloning a virtual machine fails</li> <li>Application-consistent quiescing has been enabled in Windows guest</li> <li>You see the error:<br><span style="font-family: courier;">A general system error occured: Protocol error from VMX.</span> </li> <li>In the vmware.log file, you see the error:<br><br><span style="font-family: courier;">Toolsbackup: not enough empty nodes (needed , found ).<br><br> For example:<br><br> vmx| ToolsBackup: not enough empty nodes (needed 8, found 7)<br><br> Where is the number of disks attached to the virtual machine.</span> </li> </ul><h3 data-id="cause">Cause</h3> <p>The issue occurs when the Windows server has Application-consistent quiescing enabled and the virtual machine has more than 7 disks attached to one SCSI controller.</p> <h3 data-id="resolution">Resolution</h3> <p>To resolve this issue:</p> <ul><li>Add an additional controller to the virtual machine, so that there are sufficient empty disk nodes on the controllers for the snapshots.<br><br> To add an additional controller when the virtual machine is running, add a new disk and in the Advance Options step, change the Virtual Device Node to use another controller. For example, use SCSI 1 instead of SCSI 0.<br><br> When the virtual machine is down, you can add another controller without adding a new disk. To add another controller, edit the settings of one of the existing disks and change Virtual Device Node to use a different controller.<br><br> For more information on adding an additional controller, see the <a rel="nofollow" href="/home/leaving?allowTrusted=1&target=http%3A%2F%2Fwww.vmware.com%2Fsupport%2Fpubs%2Fvs_pages%2Fvsp_pubs_esx41_vc41.html">vSphere Virtual Machine Administration Guide</a>.</li> <li>Disable application-consistent quiescing on guest OS. Set disk.EnableUUID = FALSE in the virtual machine configfuration file. For more information see <a rel="nofollow" href="/home/leaving?allowTrusted=1&target=http%3A%2F%2Fkb.vmware.com%2Fselfservice%2Fsearch.do%3Fcmd%3DdisplayKC%26docType%3Dkc%26docTypeID%3DDT_KB_1_1%26externalId%3D1028881">Enabling Windows 2008 application-consistent quiescing on ESX</a>.</li> </ul><h3 data-id="third-party-sources">Third-Party Sources</h3> <p><a rel="nofollow" href="/home/leaving?allowTrusted=1&target=http%3A%2F%2Fkb.vmware.com%2Fselfservice%2FdocumentLinkInt.do%3FmicrositeID%3D%26popup%3Dtrue%26languageId%3D%26externalID%3D1037071">http://kb.vmware.com/selfservice/documentLinkInt.do?micrositeID=&popup=true&languageId=&externalID=1037071</a></p> </article> </main>