CPU does not support long mode

mweiss · 07-12-2007, 08:18 AM

For any vmware linux users out there -

I am trying to build a RHEL4U2 64bit vm (ESX 3.1) using an iso image and keep rec'g error "CPU does not support long mode. Use a 32bit distribution". Since I have 64bit cpu's I'm thinking it's some kind of version mismatch issue.

Does anyone know - can you have a 32 bit ESX host with 64bit vm? Perhaps that is my problem, do I have to have a 64bit ESX host in order to build 64bit vm's?

thanks to anyone who has any advice!

Junior Hacker · 07-13-2007, 02:42 AM

It appears you need a 64bit host to have a 64bit guest, I don't get it, I was led to believe that vmware would allow you to run any architecture as guest from what I read on the web site. But just like you, I installed vmware in Windows XP 32bit and tried to install Debian amd64 as a guest and pretty much was told the same thing you were told. But! I also tried vmware in 64bit Debian and installed Windows Vista and XP Media Center 32bit as guests. None the less, I was not sold on the virtual thing and removed it all and will stay with the multi-boot setup as I'm not into development and only have 1GB of dual channel memory, (not enough),
EDIT: Maybe you can install 64bit vmware in a 32bit host to support a 64bit guest, maybe that's what my error was trying to tell me.

Junior Hacker · 07-13-2007, 02:46 AM

Is your CPU em64 or amd64?, because you can only install 64bit guest if the processor supports 64bit.

mweiss · 07-23-2007, 01:23 PM

UPDATE: According to vmware support these cpu's are not configured for use with virtualization... even though my AMD cpu's are in fact 64-bit they lack a certain microcode feature set needed to run 64 bit guests with VMware. There is a downloadable cpu compatibility tool from vmware that you can boot up your machine into that will check your cpu's for you.

p.s. thanks for your posts Junior