Removing the RAM limitation on ESXi 4.0.0
Wed-2009-07-08 4 Comments
I have VMWare ESXi 4.0 running in VMWare Workstation 7 (Beta). But ESXi 4.0 won’t install/start if it doesn’t run on a machine with at least 2GB RAM. This is a silly limitation if you run ESXi in VMWare Workstation though. So, let’s remove it.
- Open a console to the ESXi VM.
- Press Alt-F1 to take you to another vtty.
- Type ”unsupported”, mind you, you won’t see the input. Now press Enter.
- You will be asked for a password, type your root password
- The console should now read “You have now actived Tech Support Mode”
- Edit the esx.conf file in /etc/vmware with the command “vi /etc/vmware/esx.conf” and add the line ‘/vmkernel/minMemoryCheck = “false” ‘ to the file
- Save the file and exit the vtty.
- Press Alt-F2 again to return to the default vtty.
- Press F12, input your password, and press F2 to stop ESXi
- Adjust the amount of RAM assigned to the ESXi VM and start it again
It is said that ESX 4 (no typo) can run on 768MB. My experience is, that running on 1280MB or less, won’t even start the ESXi VM; it will crash the Purple Screen Of Death. Running 1280MB to 1664MB will run the ESXi VM, but you won’t be able to run VM’s within the ESXi VM. Running with 1664MB RAM works like a charm for me. It only gives you 384MB free RAM from 2048MB, but that might still be worth it. It does show, that VMWare’s 2048MB limitation isn’t some randomly chosen number, and I recommend not changing it if you run ESXi on a physical machine.
This trick enabled me to run another ESXi 4.0 with 1664MB within Workstation 7 (Beta), so for me it was definitely worth it =)
About Yuri de Jager
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i wont try esxi and i have the same problem
i do not understand how can edit the esx.conf if the intallation of esx don’t start for insufficent memory ( less than 2048 )
thanks Alberto
Hello Yuri, how can we do this for ESX 4.1 ? I’ve tried adding that line to the esx.config, changed the memory to 1.664 but i still receive that message stating that there is not enough memory space.
Thank you!
I’ve tested this today with ESXi 4.1 build 502767 (Update 2) on VMware Workstation 8.02 build 591240. I could boot with 1856MB RAM. Did not try to run any VM’s.
Please note that the above mentioned line won’t work in ESXi 4.1 anymore. When ESXi is rebooted, the line is removed from esx.conf. Also note VMware Workstation 8 has native support for guest operating system ESX(i).
How is this possible if the installer wont allow you to install without more RAM? It doesnt make sense…