I am currently running few VMs under vmware server 1, Now I want to switch to ESXi. How do I migrate/converts those VMs to ESXi format. Does ESXi automaticaly do the job or I have to use VMware Convertor or any tool?
No ESXi does not do it automatically - VMware converter will be the best tool to convert those VMs to the ESX environment -
I performed this exact process about a week ago. I used VMWare Converter(Free Edition) and worked perfectly. The only issue I ran into was converting thin disk vm's. Apparently converter does not keep the thin disk format and instead creates fat disks. The conversion was successful, however I did have to use the Remote CLI tools to convert back to thin. Other than that the conversion process was a breeze.
Converter seems to work for many here. But in detail, some people had problems too, for example if their VMWare Server disks have been IDE disk. A manually approch has been successfully discussed here: