I'm planning to migrate my GSX Server's VM's to ESX Server 3.0.2. Which tool or software should I use? Is there any documentation on how to do the migration?
If your VMs use virtual SCSI controllers / disks you can copy the VMDKs to the ESX host and import them there using vmkfstools.
Then create a new VM on ESX and point it to the imported disk.
When copying make sure you use a binary method and the tools used for copying can handle files bigger 2Gb.
Another option is VMware Converter.
You could also use VMware Converter software to migrate them.
That way if you used IDE disks in your GSX environment, you could change it during the procedure
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