Use 32bit OS on ESXi 4

[Hirenp09]

We have 64bit hardware and would like to use ESXi 4. This server

got 6GB total memory. Can I install 32bit version of windows and applications on

ESXi 4.0? Does anybody have comparison chart of ESXi 3.5 and ESXi 4.

Thanks

[agesen · Accepted solution]

Absolutely!

The fact that ESX 4.0 itself requires 64 bit hardware

does not limit guests to be 64 bit. You can run 16,

32 and 64 bit guests. (Just the same as was possible

with ESX 3.5.)

Best of luck.

Ole

[Troy_Clavell]

Does anybody have comparison chart of ESXi 3.5 and ESXi 4.

http://kb.vmware.com/kb/1010579

[Hirenp09]

Thanks to agesen and Troy

[bgavin1]

Reviving an old thread:

I have ESXi 4.1 running on a 4-core processor with 4gb available to ESXi.

My guest Windows 2003 servers use 512~1024mb memory.

Q: is there any reason to run 64-bit servers instead of 32-bit?

My guest VMs have no need for 64-bit memory addressing, but I'm curious if there is a Best Practice reason to run 64-bit Windows servers on ESXi.

[jb12345]

Other than 32-bit Windows approaching EOL?

[DSTAVERT]

The only reason to have 64Bit is if there is a need. If you have 64bit applications then you must use a 64bit OS. Move to 64bit when it is necessary (you need it for 64bit apps or your version is no longer supported.)

[bgavin1]

The 32-bit servers have worked well, but we have supplanted them with 2003 64-bit.

I've been rolling out Server 2008, and frankly I'd rather retire and/or drive a truck. Vista Server just plain sucks.

All that aside, my concern is if there is a performance penalty incurred using 32-bit OS under ESXi.

I don't know if the VMM runs 32-bit as emulation, or in hardware, etc.

My intial benchmarks of 2003/R2 in 32-bit show very good performance.