You don't have to do anything more than run emcgrab.exe as you would normally, and it will (attempt to) initiate the VirtualMachineInfo accessor.  However, it currently fails if you have any RawDeviceMappings.  It is easy to reproduce as follows:   1) Run the grab against an ESXi host that doesn't have any guest images containing an RDM  emcgrab.exe -host -user -password   2) You will see the VirtualMachineInfo.txt file  3) Run the grab against an ESXi host that has at least one guest image containing an RDM (or even vMotion a guest image onto the server in step 1)  4) You will see an absence of the VirtualMachineInfo.txt file  5) View the error_report.txt file in the grab output from step 4 and you'll see have something similar to the following:  ERROR - Error using accessor:com.emc.gs.tools.esxi.grab.accessor.vsphere.VirtualMachineInfo java.lang.ClassCastException: com.vmware.vim25.VirtualDiskRawDiskMappingVer1BackingInfo cannot be cast to com.vmware.vim25.VirtualDiskFlatVer2BackingInfo at com.emc.gs.tools.esxi.grab.accessor.vsphere.VirtualMachineInfo.getVirtualDisks(VirtualMachineInfo.java:95) at com.emc.gs.tools.esxi.grab.accessor.vsphere.VirtualMachineInfo.getData(VirtualMachineInfo.java:73) at com.emc.gs.tools.esxi.grab.GrabGenerator.extractVsphereInfo(GrabGenerator.java:158) at com.emc.gs.tools.esxi.grab.App.run(App.java:228) at com.emc.gs.tools.esxi.grab.App.main(App.java:145)   I have been unaware of a work-around (maybe someone else has more information?); and therefore, cannot confidently say if that would assist you in identifying all of the RDM's (either physical or virtual compatibility mode) except for the fact that you have them if you see the error.   Otherwise, if you are interested in identifying the RDM's see if the following previous post I replied to helps:  [URL]  [...] You have several options:  1) Install the Storage Viewer feature of the VSI (Virtual Storage Integrator) plug-in/framework.   Once configured, you will then see a new tab "EMC Storage" and under the Section: "Storage", you can view the Raw Device Mappings.  With the Storage Viewer feature, this gives you visibility straight through to the CLARiiON LUN/RAID Group that it resides on all within vSphere client.  [IMAGE]   2) From within Unisphere, configure the "VM-aware" feature  Once configured, this is more-or-less the inverse of the capability of the VSI, but grants you visibility from within Unisphere/Navisphere (feature since FLARE 29)  [IMAGE]   3) View the "Virtual Machine" report from the report wizard within Unisphere/Navisphere (feature since FLARE 29)  Once you configure the feature above, you can run the following report:  [IMAGE]   4) KB article: "Identifying virtual disks pointing to Raw Device Mappings (RDMs)"  [URL]  A little more work, but one way of quickly listing all of your RDM's via PowerCLI or locally on each (ESX) host querying the VMDK file metadata and piping it to vmkfstools -q; you then need to map the resulting volume identifier to the CLARiiON LUN.  This is in contrast to the strategies above which require you to click into various objects to gather the same.   Have a look at the document "EMC CLARiiON Integration with VMware ESX - Applied Technology" available from PowerLink via the following breadcrumb trail which discusses this topic:  Home > Products > Hardware/Platforms > CLARiiON CX4 Series > White Papers [...]    In addition to the suggestions above and relevant for ESXi hosts, if you also obtain the vm-support output while running the emcgrab utility,  emcgrab.exe -host -user -password -vmsupport   you will have the /vmfs directory structure along with enough of the vmdk file heads that let's you identify at least which are RawDeviceMappings by using the "find" strategy from the VMware KB article up to the point of running "xargs -L 1 vmkfstools -q" of course.  However, it is the pipe to vmkfstools -q that is only available when run directly on the console which further identifies physical versus virtual compatibility mode and also what it maps to.  Hope this helps.
Anyone know what command is run to create the “VirtualMachineInfo.txt” file found in the “/host” folder of an ESXi grab?   Trying to validate all disks associated with VM’s, and curious if RDM’s are reported in this context…   Don’t want to miss them, in planning a migration….
EMC ESXi Grab Question