I was recently setting up a test ESXi host with some spare hardware and ran in to an issue with ESXi 5.5.0 whereby I had 3.97G ram available (due to the video card using some RAM) and this was lower than the 4G requirement of ESXi.
I followed the guide at: http://community.spiceworks.com/topic/411970-installing-esxi-5-5-with-4gb-ram-memory_size-error to override this.
1. Boot from VMware ESXi 5.5;
2. wait for the “Welcome to theVMware ESXi 5.5.0 Installation” screen:
Image: //static.spiceworks.com/shared/post/0004/3520/index.jpg
3. Press Alt+F1 for enter console and login as ‘root’ (no password needed);
4. go to:
cd /usr/lib/vmware/weasel/util/
delete file:
rm upgrade_precheck.pyc;
5. remove readonly flags;
mv upgrade_precheck.py upgrade_precheck.py.def
cp upgrade_precheck.py.def upgrade_precheck.py
6. set permissions:
chmod 755 upgrade_precheck.py
7. open script in ‘vi’:
vi upgrade_precheck.py
8. type “/MEM_MIN_SIZE” to find the string “MEM_MIN_SIZE”, press “a” to enter edit mode. “(4 * 1024 – 32)” change to “(2 * 1024 – 32)”, press ‘ESC’ and then type “:wq” (save & exit);
9. look for the installer PID:
ps -c | grep weasel
10. kill the installer (PID = process number):
kill PID
The process installer process will run automatically (with modified config script).
Continue from “Welcome to theVMware ESXi 5.5.0 Installation” as usual.